heap_file.c

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/*
 * Copyright (C) 2008 Search Solution Corporation. All rights reserved by Search Solution.
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 */

/*
 * heap_file.c - heap file manager
 */

#ident "$Id$"

#if !defined(WINDOWS)
#define __STDC_FORMAT_MACROS
#include <inttypes.h>
#endif

#include "config.h"

#include <stdio.h>
#include <string.h>
#include <errno.h>

#include "heap_file.h"

#include "porting.h"
#include "slotted_page.h"
#include "overflow_file.h"
#include "boot_sr.h"
#include "locator_sr.h"
#include "btree.h"
#include "transform.h"      /* for CT_SERIAL_NAME */
#include "serial.h"
#include "object_primitive.h"
#include "xserver_interface.h"
#include "chartype.h"
#include "query_executor.h"
#include "fetch.h"
#include "server_interface.h"
#include "db_elo.h"
#include "string_opfunc.h"
#include "xasl.h"
#include "stream_to_xasl.h"
#include "query_opfunc.h"
#include "set_object.h"
#if defined(ENABLE_SYSTEMTAP)
#include "probes.h"
#endif /* ENABLE_SYSTEMTAP */
#include "dbtype.h"
#include "thread_manager.hpp"   // for thread_get_thread_entry_info

#if !defined(SERVER_MODE)
#define pthread_mutex_init(a, b)
#define pthread_mutex_destroy(a)
#define pthread_mutex_lock(a)   0
#define pthread_mutex_trylock(a)   0
#define pthread_mutex_unlock(a)
static int rv;
#endif /* not SERVER_MODE */

#define HEAP_BESTSPACE_SYNC_THRESHOLD (0.1f)

/* ATTRIBUTE LOCATION */

#define OR_FIXED_ATTRIBUTES_OFFSET_BY_OBJ(obj, nvars) \
  (OR_HEADER_SIZE(obj) + OR_VAR_TABLE_SIZE_INTERNAL(nvars, OR_GET_OFFSET_SIZE(obj)))

#define HEAP_GUESS_NUM_ATTRS_REFOIDS 100
#define HEAP_GUESS_NUM_INDEXED_ATTRS 100

#define HEAP_CLASSREPR_MAXCACHE 1024

#define HEAP_STATS_ENTRY_MHT_EST_SIZE 1000
#define HEAP_STATS_ENTRY_FREELIST_SIZE 1000

/* A good space to accept insertions */
#define HEAP_DROP_FREE_SPACE (int)(DB_PAGESIZE * 0.3)

#define HEAP_DEBUG_SCANCACHE_INITPATTERN (12345)

#if defined(CUBRID_DEBUG)
#define HEAP_DEBUG_ISVALID_SCANRANGE(scan_range) \
  heap_scanrange_isvalid(scan_range)
#else /* CUBRID_DEBUG */
#define HEAP_DEBUG_ISVALID_SCANRANGE(scan_range) (DISK_VALID)
#endif /* !CUBRID_DEBUG */

#define HEAP_IS_PAGE_OF_OID(thread_p, pgptr, oid) \
  (((pgptr) != NULL) \
   && pgbuf_get_volume_id (pgptr) == (oid)->volid \
   && pgbuf_get_page_id (pgptr) == (oid)->pageid)

#define MVCC_SET_DELETE_INFO(mvcc_delete_info_p, row_delete_id, \
                 satisfies_del_result) \
  do \
    { \
      assert ((mvcc_delete_info_p) != NULL); \
      (mvcc_delete_info_p)->row_delid = (row_delete_id); \
      (mvcc_delete_info_p)->satisfies_delete_result = (satisfies_del_result); \
    } \
  while (0)

#define HEAP_MVCC_SET_HEADER_MAXIMUM_SIZE(mvcc_rec_header_p) \
  do \
    { \
      if (!MVCC_IS_FLAG_SET (mvcc_rec_header_p, OR_MVCC_FLAG_VALID_INSID)) \
    { \
      MVCC_SET_FLAG_BITS (mvcc_rec_header_p, OR_MVCC_FLAG_VALID_INSID); \
      MVCC_SET_INSID (mvcc_rec_header_p, MVCCID_ALL_VISIBLE); \
    } \
      if (!MVCC_IS_FLAG_SET (mvcc_rec_header_p, OR_MVCC_FLAG_VALID_DELID)) \
    { \
       MVCC_SET_FLAG_BITS (mvcc_rec_header_p, OR_MVCC_FLAG_VALID_DELID); \
           MVCC_SET_DELID (mvcc_rec_header_p, MVCCID_NULL); \
    } \
      if (!MVCC_IS_FLAG_SET (mvcc_rec_header_p, OR_MVCC_FLAG_VALID_PREV_VERSION)) \
    { \
      MVCC_SET_FLAG_BITS (mvcc_rec_header_p, OR_MVCC_FLAG_VALID_PREV_VERSION); \
      LSA_SET_NULL(&(mvcc_rec_header_p)->prev_version_lsa); \
    } \
    } \
  while (0)

#if defined (SERVER_MODE)
#define HEAP_UPDATE_IS_MVCC_OP(is_mvcc_class, update_style) \
    ((is_mvcc_class) && (!HEAP_IS_UPDATE_INPLACE (update_style)) ? (true) : (false))
#else
#define HEAP_UPDATE_IS_MVCC_OP(is_mvcc_class, update_style) (false)
#endif

#define HEAP_SCAN_ORDERED_HFID(scan) \
  (((scan) != NULL) ? (&(scan)->node.hfid) : (PGBUF_ORDERED_NULL_HFID))

typedef enum
{
  HEAP_FINDSPACE_FOUND,
  HEAP_FINDSPACE_NOTFOUND,
  HEAP_FINDSPACE_ERROR
} HEAP_FINDSPACE;

/*
 * Prefetching directions
 */

typedef enum
{
  HEAP_DIRECTION_NONE,      /* No prefetching */
  HEAP_DIRECTION_LEFT,      /* Prefetching at the left */
  HEAP_DIRECTION_RIGHT,     /* Prefetching at the right */
  HEAP_DIRECTION_BOTH       /* Prefetching at both directions.. left and right */
} HEAP_DIRECTION;

/*
 * Heap file header
 */

#define HEAP_NUM_BEST_SPACESTATS   10

/* calculate an index of best array */
#define HEAP_STATS_NEXT_BEST_INDEX(i)   \
  (((i) + 1) % HEAP_NUM_BEST_SPACESTATS)
#define HEAP_STATS_PREV_BEST_INDEX(i)   \
  (((i) == 0) ? (HEAP_NUM_BEST_SPACESTATS - 1) : ((i) - 1));

typedef struct heap_hdr_stats HEAP_HDR_STATS;
struct heap_hdr_stats
{
  /* the first must be class_oid */
  OID class_oid;
  VFID ovf_vfid;        /* Overflow file identifier (if any) */
  VPID next_vpid;       /* Next page (i.e., the 2nd page of heap file) */
  int unfill_space;     /* Stop inserting when page has run below this. leave it for updates */
  struct
  {
    int num_pages;      /* Estimation of number of heap pages. Consult file manager if accurate number is
                 * needed */
    int num_recs;       /* Estimation of number of objects in heap */
    float recs_sumlen;      /* Estimation total length of records */
    int num_other_high_best;    /* Total of other believed known best pages, which are not included in the best array
                 * and we believe they have at least HEAP_DROP_FREE_SPACE */
    int num_high_best;      /* Number of pages in the best array that we believe have at least
                 * HEAP_DROP_FREE_SPACE. When this number goes to zero and there is at least other
                 * HEAP_NUM_BEST_SPACESTATS best pages, we look for them. */
    int num_substitutions;  /* Number of page substitutions. This will be used to insert a new second best page
                 * into second best hints. */
    int num_second_best;    /* Number of second best hints. The hints are in "second_best" array. They are used
                 * when finding new best pages. See the function "heap_stats_sync_bestspace". */
    int head_second_best;   /* Index of head of second best hints. */
    int tail_second_best;   /* Index of tail of second best hints. A new second best hint will be stored on this
                 * index. */
    int head;           /* Head of best circular array */
    VPID last_vpid;     /* todo: move out of estimates */
    VPID full_search_vpid;
    VPID second_best[HEAP_NUM_BEST_SPACESTATS];
    HEAP_BESTSPACE best[HEAP_NUM_BEST_SPACESTATS];
  } estimates;          /* Probably, the set of pages with more free space on the heap. Changes to any values
                 * of this array (either page or the free space for the page) are not logged since
                 * these values are only used for hints. These values may not be accurate at any given
                 * time and the entries may contain duplicated pages. */

  int reserve0_for_future;  /* Nothing reserved for future */
  int reserve1_for_future;  /* Nothing reserved for future */
  int reserve2_for_future;  /* Nothing reserved for future */
};

typedef struct heap_stats_entry HEAP_STATS_ENTRY;
struct heap_stats_entry
{
  HFID hfid;            /* heap file identifier */
  HEAP_BESTSPACE best;      /* best space info */
  HEAP_STATS_ENTRY *next;
};

/* Define heap page flags. */
#define HEAP_PAGE_FLAG_VACUUM_STATUS_MASK     0xC0000000
#define HEAP_PAGE_FLAG_VACUUM_ONCE        0x80000000
#define HEAP_PAGE_FLAG_VACUUM_UNKNOWN         0x40000000

#define HEAP_PAGE_SET_VACUUM_STATUS(chain, status) \
  do \
    { \
      assert ((status) == HEAP_PAGE_VACUUM_NONE \
          || (status) == HEAP_PAGE_VACUUM_ONCE \
          || (status) == HEAP_PAGE_VACUUM_UNKNOWN); \
      (chain)->flags &= ~HEAP_PAGE_FLAG_VACUUM_STATUS_MASK; \
      if ((status) == HEAP_PAGE_VACUUM_ONCE) \
        { \
      (chain)->flags |= HEAP_PAGE_FLAG_VACUUM_ONCE; \
    } \
      else if ((status) == HEAP_PAGE_VACUUM_UNKNOWN) \
    { \
      (chain)->flags |= HEAP_PAGE_FLAG_VACUUM_UNKNOWN; \
    } \
    } \
  while (false)

#define HEAP_PAGE_GET_VACUUM_STATUS(chain) \
  (((chain)->flags & HEAP_PAGE_FLAG_VACUUM_STATUS_MASK) == 0 \
   ? HEAP_PAGE_VACUUM_NONE \
   : ((((chain)->flags & HEAP_PAGE_FLAG_VACUUM_STATUS_MASK) \
        == HEAP_PAGE_FLAG_VACUUM_ONCE) \
      ? HEAP_PAGE_VACUUM_ONCE : HEAP_PAGE_VACUUM_UNKNOWN))

typedef struct heap_chain HEAP_CHAIN;
struct heap_chain
{               /* Double-linked */
  /* the first must be class_oid */
  OID class_oid;
  VPID prev_vpid;       /* Previous page */
  VPID next_vpid;       /* Next page */
  MVCCID max_mvccid;        /* Max MVCCID of any MVCC operations in page. */
  INT32 flags;          /* Flags for heap page. 2 bits are used for vacuum state. */
};

#define HEAP_CHK_ADD_UNFOUND_RELOCOIDS 100

typedef struct heap_chk_relocoid HEAP_CHK_RELOCOID;
struct heap_chk_relocoid
{
  OID real_oid;
  OID reloc_oid;
};

typedef struct heap_chkall_relocoids HEAP_CHKALL_RELOCOIDS;
struct heap_chkall_relocoids
{
  MHT_TABLE *ht;        /* Hash table to be used to keep relocated records The key of hash table is the
                 * relocation OID, the date is the real OID */
  bool verify;
  bool verify_not_vacuumed; /* if true then each record will be checked if it wasn't vacuumed although it must've
                 * be vacuumed */
  DISK_ISVALID not_vacuumed_res;    /* The validation result of the "not vacuumed" objects */
  int max_unfound_reloc;
  int num_unfound_reloc;
  OID *unfound_reloc_oids;  /* The relocation OIDs that have not been found in hash table */
};

#define DEFAULT_REPR_INCREMENT 16

enum
{ ZONE_VOID = 1, ZONE_FREE = 2, ZONE_LRU = 3 };

typedef struct heap_classrepr_entry HEAP_CLASSREPR_ENTRY;
struct heap_classrepr_entry
{
  pthread_mutex_t mutex;
  int idx;          /* Cache index. Used to pass the index when a class representation is in the cache */
  int fcnt;         /* How many times this structure has been fixed. It cannot be deallocated until this
                 * value is zero.  */
  int zone;         /* ZONE_VOID, ZONE_LRU, ZONE_FREE */
  int force_decache;

  THREAD_ENTRY *next_wait_thrd;
  HEAP_CLASSREPR_ENTRY *hash_next;
  HEAP_CLASSREPR_ENTRY *prev;   /* prev. entry in LRU list */
  HEAP_CLASSREPR_ENTRY *next;   /* prev. entry in LRU or free list */

  /* real data */
  OID class_oid;        /* Identifier of the class representation */

  OR_CLASSREP **repr;       /* A particular representation of the class */
  int max_reprid;
  REPR_ID last_reprid;
};

typedef struct heap_classrepr_lock HEAP_CLASSREPR_LOCK;
struct heap_classrepr_lock
{
  OID class_oid;
  HEAP_CLASSREPR_LOCK *lock_next;
  THREAD_ENTRY *next_wait_thrd;
};

typedef struct heap_classrepr_hash HEAP_CLASSREPR_HASH;
struct heap_classrepr_hash
{
  pthread_mutex_t hash_mutex;
  int idx;
  HEAP_CLASSREPR_ENTRY *hash_next;
  HEAP_CLASSREPR_LOCK *lock_next;
};

typedef struct heap_classrepr_LRU_list HEAP_CLASSREPR_LRU_LIST;
struct heap_classrepr_LRU_list
{
  pthread_mutex_t LRU_mutex;
  HEAP_CLASSREPR_ENTRY *LRU_top;
  HEAP_CLASSREPR_ENTRY *LRU_bottom;
};

typedef struct heap_classrepr_free_list HEAP_CLASSREPR_FREE_LIST;
struct heap_classrepr_free_list
{
  pthread_mutex_t free_mutex;
  HEAP_CLASSREPR_ENTRY *free_top;
  int free_cnt;
};

typedef struct heap_classrepr_cache HEAP_CLASSREPR_CACHE;
struct heap_classrepr_cache
{
  int num_entries;
  HEAP_CLASSREPR_ENTRY *area;
  int num_hash;
  HEAP_CLASSREPR_HASH *hash_table;
  HEAP_CLASSREPR_LOCK *lock_table;
  HEAP_CLASSREPR_LRU_LIST LRU_list;
  HEAP_CLASSREPR_FREE_LIST free_list;
  HFID rootclass_hfid;
#ifdef DEBUG_CLASSREPR_CACHE
  int num_fix_entries;
  pthread_mutex_t num_fix_entries_mutex;
#endif              /* DEBUG_CLASSREPR_CACHE */
};

static HEAP_CLASSREPR_CACHE heap_Classrepr_cache = {
  -1,
  NULL,
  -1,
  NULL,
  NULL,
  {
   PTHREAD_MUTEX_INITIALIZER,
   NULL,
   NULL},
  {
   PTHREAD_MUTEX_INITIALIZER,
   NULL,
   -1},
  {{NULL_FILEID, NULL_VOLID}, NULL_PAGEID}  /* rootclass_hfid */
#ifdef DEBUG_CLASSREPR_CACHE
  , 0, PTHREAD_MUTEX_INITIALIZER
#endif /* DEBUG_CLASSREPR_CACHE */
};

#define CLASSREPR_REPR_INCREMENT    10
#define CLASSREPR_HASH_SIZE  (heap_Classrepr_cache.num_entries * 2)
#define REPR_HASH(class_oid) (OID_PSEUDO_KEY(class_oid)%CLASSREPR_HASH_SIZE)

#define HEAP_MAYNEED_DECACHE_GUESSED_LASTREPRS(class_oid, hfid) \
  do \
    { \
      if (heap_Classrepr != NULL && (hfid) != NULL) \
    { \
      if (HFID_IS_NULL (&(heap_Classrepr->rootclass_hfid))) \
        (void) boot_find_root_heap (&(heap_Classrepr->rootclass_hfid)); \
      if (HFID_EQ ((hfid), &(heap_Classrepr->rootclass_hfid))) \
        (void) heap_classrepr_decache_guessed_last (class_oid); \
    } \
    } \
  while (0)

#define HEAP_CHNGUESS_FUDGE_MININDICES (100)
#define HEAP_NBITS_IN_BYTE       (8)
#define HEAP_NSHIFTS                   (3)  /* For multiplication/division by 8 */
#define HEAP_BITMASK                   (HEAP_NBITS_IN_BYTE - 1)
#define HEAP_NBITS_TO_NBYTES(bit_cnt)  \
  ((unsigned int)((bit_cnt) + HEAP_BITMASK) >> HEAP_NSHIFTS)
#define HEAP_NBYTES_TO_NBITS(byte_cnt) ((unsigned int)(byte_cnt) << HEAP_NSHIFTS)
#define HEAP_NBYTES_CLEARED(byte_ptr, byte_cnt) \
  memset((byte_ptr), '\0', (byte_cnt))
#define HEAP_BYTEOFFSET_OFBIT(bit_num) ((unsigned int)(bit_num) >> HEAP_NSHIFTS)
#define HEAP_BYTEGET(byte_ptr, bit_num) \
  ((unsigned char *)(byte_ptr) + HEAP_BYTEOFFSET_OFBIT(bit_num))

#define HEAP_BITMASK_INBYTE(bit_num)   \
  (1 << ((unsigned int)(bit_num) & HEAP_BITMASK))
#define HEAP_BIT_GET(byte_ptr, bit_num) \
  (*HEAP_BYTEGET(byte_ptr, bit_num) & HEAP_BITMASK_INBYTE(bit_num))
#define HEAP_BIT_SET(byte_ptr, bit_num) \
  (*HEAP_BYTEGET(byte_ptr, bit_num) = \
   *HEAP_BYTEGET(byte_ptr, bit_num) | HEAP_BITMASK_INBYTE(bit_num))
#define HEAP_BIT_CLEAR(byte_ptr, bit_num) \
  (*HEAP_BYTEGET(byte_ptr, bit_num) = \
   *HEAP_BYTEGET(byte_ptr, bit_num) & ~HEAP_BITMASK_INBYTE(bit_num))

typedef struct heap_chnguess_entry HEAP_CHNGUESS_ENTRY;
struct heap_chnguess_entry
{               /* Currently, only classes are cached */
  int idx;          /* Index number of this entry */
  int chn;          /* Cache coherence number of object */
  bool recently_accessed;   /* Reference value 0/1 used by replacement clock algorithm */
  OID oid;          /* Identifier of object */
  unsigned char *bits;      /* Bit index array describing client transaction indices. Bit n corresponds to client
                 * tran index n If Bit is ON, we guess that the object is cached in the workspace of
                 * the client. */
};

typedef struct heap_chnguess HEAP_CHNGUESS;
struct heap_chnguess
{
  MHT_TABLE *ht;        /* Hash table for guessing chn */
  HEAP_CHNGUESS_ENTRY *entries; /* Pointers to entry structures. More than one entry */
  unsigned char *bitindex;  /* Bit index array for each entry. Describe all entries. Each entry is subdivided into
                 * nbytes. */
  bool schema_change;       /* Has the schema been changed */
  int clock_hand;       /* Clock hand for replacement */
  int num_entries;      /* Number of guesschn entries */
  int num_clients;      /* Number of clients in bitindex for each entry */
  int nbytes;           /* Number of bytes in bitindex. It must be aligned to multiples of 4 bytes (integers) */
};

typedef struct heap_stats_bestspace_cache HEAP_STATS_BESTSPACE_CACHE;
struct heap_stats_bestspace_cache
{
  int num_stats_entries;    /* number of cache entries in use */
  MHT_TABLE *hfid_ht;       /* HFID Hash table for best space */
  MHT_TABLE *vpid_ht;       /* VPID Hash table for best space */
  int num_alloc;
  int num_free;
  int free_list_count;      /* number of entries in free */
  HEAP_STATS_ENTRY *free_list;
  pthread_mutex_t bestspace_mutex;
};

typedef struct heap_show_scan_ctx HEAP_SHOW_SCAN_CTX;
struct heap_show_scan_ctx
{
  HFID *hfids;          /* Array of class HFID */
  int hfids_count;      /* Count of above hfids array */
};

static int heap_Maxslotted_reclength;
static int heap_Slotted_overhead = 4;   /* sizeof (SPAGE_SLOT) */
static const int heap_Find_best_page_limit = 100;

static HEAP_CLASSREPR_CACHE *heap_Classrepr = NULL;
static HEAP_CHNGUESS heap_Guesschn_area = { NULL, NULL, NULL, false, 0,
  0, 0, 0
};

static HEAP_CHNGUESS *heap_Guesschn = NULL;

static HEAP_STATS_BESTSPACE_CACHE heap_Bestspace_cache_area =
  { 0, NULL, NULL, 0, 0, 0, NULL, PTHREAD_MUTEX_INITIALIZER };

static HEAP_STATS_BESTSPACE_CACHE *heap_Bestspace = NULL;

static HEAP_HFID_TABLE heap_Hfid_table_area = { LF_HASH_TABLE_INITIALIZER, LF_ENTRY_DESCRIPTOR_INITIALIZER,
  LF_FREELIST_INITIALIZER
};

static HEAP_HFID_TABLE *heap_Hfid_table = NULL;

/* Recovery. */
#define HEAP_RV_FLAG_VACUUM_STATUS_CHANGE 0x8000

#define HEAP_PERF_START(thread_p, context) \
  PERF_UTIME_TRACKER_START (thread_p, (context)->time_track)
#define HEAP_PERF_TRACK_PREPARE(thread_p, context) \
  do \
    { \
      if ((context)->time_track == NULL) break; \
      switch ((context)->type) { \
      case HEAP_OPERATION_INSERT: \
    PERF_UTIME_TRACKER_ADD_TIME_AND_RESTART (thread_p, (context)->time_track, PSTAT_HEAP_INSERT_PREPARE); \
    break; \
      case HEAP_OPERATION_DELETE: \
    PERF_UTIME_TRACKER_ADD_TIME_AND_RESTART (thread_p, (context)->time_track, PSTAT_HEAP_DELETE_PREPARE); \
    break; \
      case HEAP_OPERATION_UPDATE: \
    PERF_UTIME_TRACKER_ADD_TIME_AND_RESTART (thread_p, (context)->time_track, PSTAT_HEAP_UPDATE_PREPARE); \
    break; \
      default: \
    assert (false); \
      } \
    } \
  while (false)
#define HEAP_PERF_TRACK_EXECUTE(thread_p, context) \
  do \
    { \
      if ((context)->time_track == NULL) break; \
      switch ((context)->type) { \
      case HEAP_OPERATION_INSERT: \
    PERF_UTIME_TRACKER_ADD_TIME_AND_RESTART (thread_p, \
                         (context)->time_track,\
                         PSTAT_HEAP_INSERT_EXECUTE); \
    break; \
      case HEAP_OPERATION_DELETE: \
    PERF_UTIME_TRACKER_ADD_TIME_AND_RESTART (thread_p, (context)->time_track, PSTAT_HEAP_DELETE_EXECUTE); \
    break; \
      case HEAP_OPERATION_UPDATE: \
    PERF_UTIME_TRACKER_ADD_TIME_AND_RESTART (thread_p, (context)->time_track, PSTAT_HEAP_UPDATE_EXECUTE); \
    break; \
      default: \
    assert (false); \
      } \
    } \
  while (false)
#define HEAP_PERF_TRACK_LOGGING(thread_p, context) \
  do \
    { \
      if ((context)->time_track == NULL) break; \
      switch ((context)->type) { \
      case HEAP_OPERATION_INSERT: \
    PERF_UTIME_TRACKER_ADD_TIME_AND_RESTART (thread_p, (context)->time_track, PSTAT_HEAP_INSERT_LOG); \
    break; \
      case HEAP_OPERATION_DELETE: \
    PERF_UTIME_TRACKER_ADD_TIME_AND_RESTART (thread_p, (context)->time_track, PSTAT_HEAP_DELETE_LOG); \
    break; \
      case HEAP_OPERATION_UPDATE: \
    PERF_UTIME_TRACKER_ADD_TIME_AND_RESTART (thread_p, (context)->time_track, PSTAT_HEAP_UPDATE_LOG); \
    break; \
      default: \
    assert (false); \
      } \
    } \
  while (false)

#if defined (NDEBUG)
static PAGE_PTR heap_scan_pb_lock_and_fetch (THREAD_ENTRY * thread_p, const VPID * vpid_ptr, PAGE_FETCH_MODE fetch_mode,
                         LOCK lock, HEAP_SCANCACHE * scan_cache, PGBUF_WATCHER * pg_watcher);
#else /* !NDEBUG */
#define heap_scan_pb_lock_and_fetch(...) \
  heap_scan_pb_lock_and_fetch_debug (__VA_ARGS__, ARG_FILE_LINE)

static PAGE_PTR heap_scan_pb_lock_and_fetch_debug (THREAD_ENTRY * thread_p, const VPID * vpid_ptr,
                           PAGE_FETCH_MODE fetch_mode, LOCK lock, HEAP_SCANCACHE * scan_cache,
                           PGBUF_WATCHER * pg_watcher, const char *caller_file,
                           const int caller_line);
#endif /* !NDEBUG */


static int heap_classrepr_initialize_cache (void);
static int heap_classrepr_finalize_cache (void);
static int heap_classrepr_decache_guessed_last (const OID * class_oid);
#ifdef SERVER_MODE
static int heap_classrepr_lock_class (THREAD_ENTRY * thread_p, HEAP_CLASSREPR_HASH * hash_anchor,
                      const OID * class_oid);
static int heap_classrepr_unlock_class (HEAP_CLASSREPR_HASH * hash_anchor, const OID * class_oid, int need_hash_mutex);
#endif

static int heap_classrepr_dump (THREAD_ENTRY * thread_p, FILE * fp, const OID * class_oid, const OR_CLASSREP * repr);
#ifdef DEBUG_CLASSREPR_CACHE
static int heap_classrepr_dump_cache (bool simple_dump);
#endif /* DEBUG_CLASSREPR_CACHE */

static int heap_classrepr_entry_reset (HEAP_CLASSREPR_ENTRY * cache_entry);
static int heap_classrepr_entry_remove_from_LRU (HEAP_CLASSREPR_ENTRY * cache_entry);
static HEAP_CLASSREPR_ENTRY *heap_classrepr_entry_alloc (void);
static int heap_classrepr_entry_free (HEAP_CLASSREPR_ENTRY * cache_entry);

static OR_CLASSREP *heap_classrepr_get_from_record (THREAD_ENTRY * thread_p, REPR_ID * last_reprid,
                            const OID * class_oid, RECDES * class_recdes, REPR_ID reprid);
static int heap_stats_get_min_freespace (HEAP_HDR_STATS * heap_hdr);
static int heap_stats_update_internal (THREAD_ENTRY * thread_p, const HFID * hfid, VPID * lotspace_vpid,
                       int free_space);
static void heap_stats_put_second_best (HEAP_HDR_STATS * heap_hdr, VPID * vpid);
static int heap_stats_get_second_best (HEAP_HDR_STATS * heap_hdr, VPID * vpid);
#if defined(ENABLE_UNUSED_FUNCTION)
static int heap_stats_quick_num_fit_in_bestspace (HEAP_BESTSPACE * bestspace, int num_entries, int unit_size,
                          int unfill_space);
#endif
static HEAP_FINDSPACE heap_stats_find_page_in_bestspace (THREAD_ENTRY * thread_p, const HFID * hfid,
                             HEAP_BESTSPACE * bestspace, int *idx_badspace,
                             int record_length, int needed_space,
                             HEAP_SCANCACHE * scan_cache, PGBUF_WATCHER * pg_watcher);
static PAGE_PTR heap_stats_find_best_page (THREAD_ENTRY * thread_p, const HFID * hfid, int needed_space, bool isnew_rec,
                       int newrec_size, HEAP_SCANCACHE * space_cache, PGBUF_WATCHER * pg_watcher);
static int heap_stats_sync_bestspace (THREAD_ENTRY * thread_p, const HFID * hfid, HEAP_HDR_STATS * heap_hdr,
                      VPID * hdr_vpid, bool scan_all, bool can_cycle);

static int heap_get_last_page (THREAD_ENTRY * thread_p, const HFID * hfid, HEAP_HDR_STATS * heap_hdr,
                   HEAP_SCANCACHE * scan_cache, VPID * last_vpid, PGBUF_WATCHER * pg_watcher);

static int heap_vpid_init_new (THREAD_ENTRY * thread_p, PAGE_PTR page, void *args);
static int heap_vpid_alloc (THREAD_ENTRY * thread_p, const HFID * hfid, PAGE_PTR hdr_pgptr, HEAP_HDR_STATS * heap_hdr,
                HEAP_SCANCACHE * scan_cache, PGBUF_WATCHER * new_pg_watcher);
static VPID *heap_vpid_remove (THREAD_ENTRY * thread_p, const HFID * hfid, HEAP_HDR_STATS * heap_hdr, VPID * rm_vpid);

static int heap_create_internal (THREAD_ENTRY * thread_p, HFID * hfid, const OID * class_oid, const bool reuse_oid);
static const HFID *heap_reuse (THREAD_ENTRY * thread_p, const HFID * hfid, const OID * class_oid, const bool reuse_oid);
static bool heap_delete_all_page_records (THREAD_ENTRY * thread_p, const VPID * vpid, PAGE_PTR pgptr);
static int heap_reinitialize_page (THREAD_ENTRY * thread_p, PAGE_PTR pgptr, const bool is_header_page);
#if defined(CUBRID_DEBUG)
static DISK_ISVALID heap_hfid_isvalid (HFID * hfid);
static DISK_ISVALID heap_scanrange_isvalid (HEAP_SCANRANGE * scan_range);
#endif /* CUBRID_DEBUG */
static OID *heap_ovf_insert (THREAD_ENTRY * thread_p, const HFID * hfid, OID * ovf_oid, RECDES * recdes);
static const OID *heap_ovf_update (THREAD_ENTRY * thread_p, const HFID * hfid, const OID * ovf_oid, RECDES * recdes);
static int heap_ovf_flush (THREAD_ENTRY * thread_p, const OID * ovf_oid);
static int heap_ovf_get_length (THREAD_ENTRY * thread_p, const OID * ovf_oid);
static SCAN_CODE heap_ovf_get (THREAD_ENTRY * thread_p, const OID * ovf_oid, RECDES * recdes, int chn,
                   MVCC_SNAPSHOT * mvcc_snapshot);
static int heap_ovf_get_capacity (THREAD_ENTRY * thread_p, const OID * ovf_oid, int *ovf_len, int *ovf_num_pages,
                  int *ovf_overhead, int *ovf_free_space);

static int heap_scancache_check_with_hfid (THREAD_ENTRY * thread_p, HFID * hfid, OID * class_oid,
                       HEAP_SCANCACHE ** scan_cache);
static int heap_scancache_start_internal (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, const HFID * hfid,
                      const OID * class_oid, int cache_last_fix_page, bool is_queryscan,
                      int is_indexscan, MVCC_SNAPSHOT * mvcc_snapshot);
static int heap_scancache_force_modify (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache);
static int heap_scancache_reset_modify (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, const HFID * hfid,
                    const OID * class_oid);
static int heap_scancache_quick_start_internal (HEAP_SCANCACHE * scan_cache, const HFID * hfid);
static int heap_scancache_quick_end (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache);
static int heap_scancache_end_internal (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, bool scan_state);
static SCAN_CODE heap_get_if_diff_chn (THREAD_ENTRY * thread_p, PAGE_PTR pgptr, INT16 slotid, RECDES * recdes,
                       bool ispeeking, int chn, MVCC_SNAPSHOT * mvcc_snapshot);
static int heap_estimate_avg_length (THREAD_ENTRY * thread_p, const HFID * hfid);
static int heap_get_capacity (THREAD_ENTRY * thread_p, const HFID * hfid, INT64 * num_recs, INT64 * num_recs_relocated,
                  INT64 * num_recs_inovf, INT64 * num_pages, int *avg_freespace, int *avg_freespace_nolast,
                  int *avg_reclength, int *avg_overhead);
#if 0               /* TODO: remove unused */
static int heap_moreattr_attrinfo (int attrid, HEAP_CACHE_ATTRINFO * attr_info);
#endif

static int heap_attrinfo_recache_attrepr (HEAP_CACHE_ATTRINFO * attr_info, bool islast_reset);
static int heap_attrinfo_recache (THREAD_ENTRY * thread_p, REPR_ID reprid, HEAP_CACHE_ATTRINFO * attr_info);
static int heap_attrinfo_check (const OID * inst_oid, HEAP_CACHE_ATTRINFO * attr_info);
static int heap_attrinfo_set_uninitialized (THREAD_ENTRY * thread_p, OID * inst_oid, RECDES * recdes,
                        HEAP_CACHE_ATTRINFO * attr_info);
static int heap_attrinfo_start_refoids (THREAD_ENTRY * thread_p, OID * class_oid, HEAP_CACHE_ATTRINFO * attr_info);
static int heap_attrinfo_get_disksize (HEAP_CACHE_ATTRINFO * attr_info, bool is_mvcc_class, int *offset_size_ptr);

static int heap_attrvalue_read (RECDES * recdes, HEAP_ATTRVALUE * value, HEAP_CACHE_ATTRINFO * attr_info);

static int heap_midxkey_get_value (RECDES * recdes, OR_ATTRIBUTE * att, DB_VALUE * value,
                   HEAP_CACHE_ATTRINFO * attr_info);
static OR_ATTRIBUTE *heap_locate_attribute (ATTR_ID attrid, HEAP_CACHE_ATTRINFO * attr_info);

static DB_MIDXKEY *heap_midxkey_key_get (RECDES * recdes, DB_MIDXKEY * midxkey, OR_INDEX * index,
                     HEAP_CACHE_ATTRINFO * attrinfo, DB_VALUE * func_res, TP_DOMAIN * func_domain,
                     TP_DOMAIN ** key_domain);
static DB_MIDXKEY *heap_midxkey_key_generate (THREAD_ENTRY * thread_p, RECDES * recdes, DB_MIDXKEY * midxkey,
                          int *att_ids, HEAP_CACHE_ATTRINFO * attrinfo, DB_VALUE * func_res,
                          int func_col_id, int func_attr_index_start);

static int heap_dump_hdr (FILE * fp, HEAP_HDR_STATS * heap_hdr);

static int heap_eval_function_index (THREAD_ENTRY * thread_p, FUNCTION_INDEX_INFO * func_index_info, int n_atts,
                     int *att_ids, HEAP_CACHE_ATTRINFO * attr_info, RECDES * recdes, int btid_index,
                     DB_VALUE * result, FUNC_PRED_UNPACK_INFO * func_pred, TP_DOMAIN ** fi_domain);

static DISK_ISVALID heap_check_all_pages_by_heapchain (THREAD_ENTRY * thread_p, HFID * hfid,
                               HEAP_CHKALL_RELOCOIDS * chk_objs, INT32 * num_checked);

#if defined (SA_MODE)
static DISK_ISVALID heap_check_all_pages_by_file_table (THREAD_ENTRY * thread_p, HFID * hfid,
                            HEAP_CHKALL_RELOCOIDS * chk_objs);
static int heap_file_map_chkreloc (THREAD_ENTRY * thread_p, PAGE_PTR * page, bool * stop, void *args);
#endif /* SA_MODE */

static DISK_ISVALID heap_chkreloc_start (HEAP_CHKALL_RELOCOIDS * chk);
static DISK_ISVALID heap_chkreloc_end (HEAP_CHKALL_RELOCOIDS * chk);
static int heap_chkreloc_print_notfound (const void *ignore_reloc_oid, void *ent, void *xchk);
static DISK_ISVALID heap_chkreloc_next (THREAD_ENTRY * thread_p, HEAP_CHKALL_RELOCOIDS * chk, PAGE_PTR pgptr);

static int heap_chnguess_initialize (void);
static int heap_chnguess_realloc (void);
static int heap_chnguess_finalize (void);
static int heap_chnguess_decache (const OID * oid);
static int heap_chnguess_remove_entry (const void *oid_key, void *ent, void *xignore);

static int heap_stats_bestspace_initialize (void);
static int heap_stats_bestspace_finalize (void);

static int heap_get_spage_type (void);
static bool heap_is_reusable_oid (const FILE_TYPE file_type);

static SCAN_CODE heap_attrinfo_transform_to_disk_internal (THREAD_ENTRY * thread_p, HEAP_CACHE_ATTRINFO * attr_info,
                               RECDES * old_recdes, RECDES * new_recdes,
                               int lob_create_flag);
static int heap_stats_del_bestspace_by_vpid (THREAD_ENTRY * thread_p, VPID * vpid);
static int heap_stats_del_bestspace_by_hfid (THREAD_ENTRY * thread_p, const HFID * hfid);
static HEAP_BESTSPACE heap_stats_get_bestspace_by_vpid (THREAD_ENTRY * thread_p, VPID * vpid);
static HEAP_STATS_ENTRY *heap_stats_add_bestspace (THREAD_ENTRY * thread_p, const HFID * hfid, VPID * vpid,
                           int freespace);
static int heap_stats_entry_free (THREAD_ENTRY * thread_p, void *data, void *args);
static int heap_get_partitions_from_subclasses (THREAD_ENTRY * thread_p, const OID * subclasses, int *parts_count,
                        OR_PARTITION * partitions);
static int heap_class_get_partition_info (THREAD_ENTRY * thread_p, const OID * class_oid, OR_PARTITION * partition_info,
                      HFID * class_hfid, REPR_ID * repr_id, int *has_partition_info);
static int heap_get_partition_attributes (THREAD_ENTRY * thread_p, const OID * cls_oid, ATTR_ID * type_id,
                      ATTR_ID * values_id);
static int heap_get_class_subclasses (THREAD_ENTRY * thread_p, const OID * class_oid, int *count, OID ** subclasses);

static unsigned int heap_hash_vpid (const void *key_vpid, unsigned int htsize);
static int heap_compare_vpid (const void *key_vpid1, const void *key_vpid2);
static unsigned int heap_hash_hfid (const void *key_hfid, unsigned int htsize);
static int heap_compare_hfid (const void *key_hfid1, const void *key_hfid2);

static char *heap_bestspace_to_string (char *buf, int buf_size, const HEAP_BESTSPACE * hb);

static int fill_string_to_buffer (char **start, char *end, const char *str);

static SCAN_CODE heap_get_record_info (THREAD_ENTRY * thread_p, const OID oid, RECDES * recdes, RECDES forward_recdes,
                       PGBUF_WATCHER * page_watcher, HEAP_SCANCACHE * scan_cache, bool ispeeking,
                       DB_VALUE ** record_info);
static SCAN_CODE heap_next_internal (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, OID * next_oid,
                     RECDES * recdes, HEAP_SCANCACHE * scan_cache, bool ispeeking,
                     bool reversed_direction, DB_VALUE ** cache_recordinfo);

static SCAN_CODE heap_get_page_info (THREAD_ENTRY * thread_p, const OID * cls_oid, const HFID * hfid, const VPID * vpid,
                     const PAGE_PTR pgptr, DB_VALUE ** page_info);
static int heap_scancache_start_chain_update (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * new_scan_cache,
                          HEAP_SCANCACHE * old_scan_cache, OID * next_row_version);
static SCAN_CODE heap_get_bigone_content (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, bool ispeeking,
                      OID * forward_oid, RECDES * recdes);
static void heap_mvcc_log_insert (THREAD_ENTRY * thread_p, RECDES * p_recdes, LOG_DATA_ADDR * p_addr);
static void heap_mvcc_log_delete (THREAD_ENTRY * thread_p, LOG_DATA_ADDR * p_addr, LOG_RCVINDEX rcvindex);
static int heap_rv_mvcc_redo_delete_internal (THREAD_ENTRY * thread_p, PAGE_PTR page, PGSLOTID slotid, MVCCID mvccid);
static void heap_mvcc_log_home_change_on_delete (THREAD_ENTRY * thread_p, RECDES * old_recdes, RECDES * new_recdes,
                         LOG_DATA_ADDR * p_addr);
static void heap_mvcc_log_home_no_change (THREAD_ENTRY * thread_p, LOG_DATA_ADDR * p_addr);

static void heap_mvcc_log_redistribute (THREAD_ENTRY * thread_p, RECDES * p_recdes, LOG_DATA_ADDR * p_addr);

#if defined(ENABLE_UNUSED_FUNCTION)
static INLINE int heap_try_fetch_header_page (THREAD_ENTRY * thread_p, PAGE_PTR * home_pgptr_p,
                          const VPID * home_vpid_p, const OID * oid_p, PAGE_PTR * hdr_pgptr_p,
                          const VPID * hdr_vpid_p, HEAP_SCANCACHE * scan_cache, int *again_count,
                          int again_max) __attribute__ ((ALWAYS_INLINE));
static INLINE int heap_try_fetch_forward_page (THREAD_ENTRY * thread_p, PAGE_PTR * home_pgptr_p,
                           const VPID * home_vpid_p, const OID * oid_p, PAGE_PTR * fwd_pgptr_p,
                           const VPID * fwd_vpid_p, const OID * fwd_oid_p,
                           HEAP_SCANCACHE * scan_cache, int *again_count, int again_max)
  __attribute__ ((ALWAYS_INLINE));
static INLINE int heap_try_fetch_header_with_forward_page (THREAD_ENTRY * thread_p, PAGE_PTR * home_pgptr_p,
                               const VPID * home_vpid_p, const OID * oid_p,
                               PAGE_PTR * hdr_pgptr_p, const VPID * hdr_vpid_p,
                               PAGE_PTR * fwd_pgptr_p, const VPID * fwd_vpid_p,
                               const OID * fwd_oid_p, HEAP_SCANCACHE * scan_cache,
                               int *again_count, int again_max)
  __attribute__ ((ALWAYS_INLINE));
#endif /* ENABLE_UNUSED_FUNCTION */

/* common */
static void heap_link_watchers (HEAP_OPERATION_CONTEXT * child, HEAP_OPERATION_CONTEXT * parent);
static void heap_unfix_watchers (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context);
static void heap_clear_operation_context (HEAP_OPERATION_CONTEXT * context, HFID * hfid_p);
static int heap_mark_class_as_modified (THREAD_ENTRY * thread_p, OID * oid_p, int chn, bool decache);
static FILE_TYPE heap_get_file_type (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context);
static int heap_is_valid_oid (THREAD_ENTRY * thread_p, OID * oid);
static int heap_fix_header_page (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context);
static int heap_fix_forward_page (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, OID * forward_oid_hint);
static void heap_build_forwarding_recdes (RECDES * recdes_p, INT16 rec_type, OID * forward_oid);

/* heap insert related functions */
static int heap_insert_adjust_recdes_header (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context,
                         bool is_mvcc_class);
static int heap_update_adjust_recdes_header (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * update_context,
                         bool is_mvcc_class);
static int heap_insert_handle_multipage_record (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context);
static int heap_get_insert_location_with_lock (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context,
                           PGBUF_WATCHER * home_hint_p);
static int heap_find_location_and_insert_rec_newhome (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context);
static int heap_insert_newhome (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * parent_context, RECDES * recdes_p,
                OID * out_oid_p, PGBUF_WATCHER * newhome_pg_watcher);
static int heap_insert_physical (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context);
static void heap_log_insert_physical (THREAD_ENTRY * thread_p, PAGE_PTR page_p, VFID * vfid_p, OID * oid_p,
                      RECDES * recdes_p, bool is_mvcc_op, bool is_redistribute_op);

/* heap delete related functions */
static void heap_delete_adjust_header (MVCC_REC_HEADER * header_p, MVCCID mvcc_id, bool need_mvcc_header_max_size);
static int heap_get_record_location (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context);
static int heap_delete_bigone (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op);
static int heap_delete_relocation (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op);
static int heap_delete_home (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op);
static int heap_delete_physical (THREAD_ENTRY * thread_p, HFID * hfid_p, PAGE_PTR page_p, OID * oid_p);
static void heap_log_delete_physical (THREAD_ENTRY * thread_p, PAGE_PTR page_p, VFID * vfid_p, OID * oid_p,
                      RECDES * recdes_p, bool mark_reusable, LOG_LSA * undo_lsa);

/* heap update related functions */
static int heap_update_bigone (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op);
static int heap_update_relocation (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op);
static int heap_update_home (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op);
static int heap_update_physical (THREAD_ENTRY * thread_p, PAGE_PTR page_p, short slot_id, RECDES * recdes_p);
static void heap_log_update_physical (THREAD_ENTRY * thread_p, PAGE_PTR page_p, VFID * vfid_p, OID * oid_p,
                      RECDES * old_recdes_p, RECDES * new_recdes_p, LOG_RCVINDEX rcvindex);

static void *heap_hfid_table_entry_alloc (void);
static int heap_hfid_table_entry_free (void *unique_stat);
static int heap_hfid_table_entry_init (void *unique_stat);
static int heap_hfid_table_entry_key_copy (void *src, void *dest);
static unsigned int heap_hfid_table_entry_key_hash (void *key, int hash_table_size);
static int heap_hfid_table_entry_key_compare (void *k1, void *k2);
static int heap_hfid_cache_get (THREAD_ENTRY * thread_p, const OID * class_oid, HFID * hfid, FILE_TYPE * ftype_out);
static int heap_get_hfid_from_class_record (THREAD_ENTRY * thread_p, const OID * class_oid, HFID * hfid);

static void heap_page_update_chain_after_mvcc_op (THREAD_ENTRY * thread_p, PAGE_PTR heap_page, MVCCID mvccid);
static void heap_page_rv_chain_update (THREAD_ENTRY * thread_p, PAGE_PTR heap_page, MVCCID mvccid,
                       bool vacuum_status_change);

static int heap_scancache_add_partition_node (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache,
                          OID * partition_oid);
static SCAN_CODE heap_get_visible_version_from_log (THREAD_ENTRY * thread_p, RECDES * recdes,
                            LOG_LSA * previous_version_lsa, HEAP_SCANCACHE * scan_cache,
                            int has_chn);
static int heap_update_set_prev_version (THREAD_ENTRY * thread_p, const OID * oid, PGBUF_WATCHER * home_pg_watcher,
                     PGBUF_WATCHER * fwd_pg_watcher, LOG_LSA * prev_version_lsa);
static int heap_scan_cache_allocate_recdes_data (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache_p,
                         RECDES * recdes_p, int size);

static int heap_get_header_page (THREAD_ENTRY * thread_p, const HFID * hfid, VPID * header_vpid);

STATIC_INLINE HEAP_HDR_STATS *heap_get_header_stats_ptr (THREAD_ENTRY * thread_p, PAGE_PTR page_header)
  __attribute__ ((ALWAYS_INLINE));
STATIC_INLINE int heap_copy_header_stats (THREAD_ENTRY * thread_p, PAGE_PTR page_header, HEAP_HDR_STATS * header_stats)
  __attribute__ ((ALWAYS_INLINE));
STATIC_INLINE HEAP_CHAIN *heap_get_chain_ptr (THREAD_ENTRY * thread_p, PAGE_PTR page_heap)
  __attribute__ ((ALWAYS_INLINE));
STATIC_INLINE int heap_copy_chain (THREAD_ENTRY * thread_p, PAGE_PTR page_heap, HEAP_CHAIN * chain)
  __attribute__ ((ALWAYS_INLINE));
STATIC_INLINE int heap_get_last_vpid (THREAD_ENTRY * thread_p, const HFID * hfid, VPID * last_vpid)
  __attribute__ ((ALWAYS_INLINE));

/*
 * heap_hash_vpid () - Hash a page identifier
 *   return: hash value
 *   key_vpid(in): VPID to hash
 *   htsize(in): Size of hash table
 */
static unsigned int
heap_hash_vpid (const void *key_vpid, unsigned int htsize)
{
  const VPID *vpid = (VPID *) key_vpid;

  return ((vpid->pageid | ((unsigned int) vpid->volid) << 24) % htsize);
}

/*
 * heap_compare_vpid () - Compare two vpids keys for hashing
 *   return: int (key_vpid1 == key_vpid2 ?)
 *   key_vpid1(in): First key
 *   key_vpid2(in): Second key
 */
static int
heap_compare_vpid (const void *key_vpid1, const void *key_vpid2)
{
  const VPID *vpid1 = (VPID *) key_vpid1;
  const VPID *vpid2 = (VPID *) key_vpid2;

  return VPID_EQ (vpid1, vpid2);
}

/*
 * heap_hash_hfid () - Hash a file identifier
 *   return: hash value
 *   key_hfid(in): HFID to hash
 *   htsize(in): Size of hash table
 */
static unsigned int
heap_hash_hfid (const void *key_hfid, unsigned int htsize)
{
  const HFID *hfid = (HFID *) key_hfid;

  return ((hfid->hpgid | ((unsigned int) hfid->vfid.volid) << 24) % htsize);
}

/*
 * heap_compare_hfid () - Compare two hfids keys for hashing
 *   return: int (key_hfid1 == key_hfid2 ?)
 *   key_hfid1(in): First key
 *   key_hfid2(in): Second key
 */
static int
heap_compare_hfid (const void *key_hfid1, const void *key_hfid2)
{
  const HFID *hfid1 = (HFID *) key_hfid1;
  const HFID *hfid2 = (HFID *) key_hfid2;

  return HFID_EQ (hfid1, hfid2);
}

/*
 * heap_stats_entry_free () - release all memory occupied by an best space
 *   return:  NO_ERROR
 *   data(in): a best space associated with the key
 *   args(in): NULL (not used here, but needed by mht_map)
 */
static int
heap_stats_entry_free (THREAD_ENTRY * thread_p, void *data, void *args)
{
  HEAP_STATS_ENTRY *ent;

  ent = (HEAP_STATS_ENTRY *) data;
  assert_release (ent != NULL);

  if (ent)
    {
      if (heap_Bestspace->free_list_count < HEAP_STATS_ENTRY_FREELIST_SIZE)
    {
      ent->next = heap_Bestspace->free_list;
      heap_Bestspace->free_list = ent;

      heap_Bestspace->free_list_count++;
    }
      else
    {
      free_and_init (ent);

      heap_Bestspace->num_free++;
    }
    }

  return NO_ERROR;
}

/*
 * heap_stats_add_bestspace () -
 */
static HEAP_STATS_ENTRY *
heap_stats_add_bestspace (THREAD_ENTRY * thread_p, const HFID * hfid, VPID * vpid, int freespace)
{
  HEAP_STATS_ENTRY *ent;
  int rc;

  assert (prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES) > 0);

  rc = pthread_mutex_lock (&heap_Bestspace->bestspace_mutex);

  ent = (HEAP_STATS_ENTRY *) mht_get (heap_Bestspace->vpid_ht, vpid);

  if (ent)
    {
      ent->best.freespace = freespace;
      goto end;
    }

  if (heap_Bestspace->num_stats_entries >= prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES))
    {
      er_set (ER_NOTIFICATION_SEVERITY, ARG_FILE_LINE, ER_HF_MAX_BESTSPACE_ENTRIES, 1,
          prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES));

      perfmon_inc_stat (thread_p, PSTAT_HF_NUM_STATS_MAXED);


      ent = NULL;
      goto end;
    }

  if (heap_Bestspace->free_list_count > 0)
    {
      assert_release (heap_Bestspace->free_list != NULL);

      ent = heap_Bestspace->free_list;
      if (ent == NULL)
    {
      goto end;
    }
      heap_Bestspace->free_list = ent->next;
      ent->next = NULL;

      heap_Bestspace->free_list_count--;
    }
  else
    {
      ent = (HEAP_STATS_ENTRY *) malloc (sizeof (HEAP_STATS_ENTRY));
      if (ent == NULL)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, sizeof (HEAP_STATS_ENTRY));

      goto end;
    }

      heap_Bestspace->num_alloc++;
    }

  HFID_COPY (&ent->hfid, hfid);
  ent->best.vpid = *vpid;
  ent->best.freespace = freespace;
  ent->next = NULL;

  if (mht_put (heap_Bestspace->vpid_ht, &ent->best.vpid, ent) == NULL)
    {
      assert_release (false);
      (void) heap_stats_entry_free (thread_p, ent, NULL);
      ent = NULL;
      goto end;
    }

  if (mht_put_new (heap_Bestspace->hfid_ht, &ent->hfid, ent) == NULL)
    {
      assert_release (false);
      (void) mht_rem (heap_Bestspace->vpid_ht, &ent->best.vpid, NULL, NULL);
      (void) heap_stats_entry_free (thread_p, ent, NULL);
      ent = NULL;
      goto end;
    }

  heap_Bestspace->num_stats_entries++;

end:

  assert (mht_count (heap_Bestspace->vpid_ht) == mht_count (heap_Bestspace->hfid_ht));

  pthread_mutex_unlock (&heap_Bestspace->bestspace_mutex);

  return ent;
}

/*
 * heap_stats_del_bestspace_by_hfid () -
 *   return: deleted count
 *
 *   hfid(in):
 */
static int
heap_stats_del_bestspace_by_hfid (THREAD_ENTRY * thread_p, const HFID * hfid)
{
  HEAP_STATS_ENTRY *ent;
  int del_cnt = 0;
  int rc;

  rc = pthread_mutex_lock (&heap_Bestspace->bestspace_mutex);

  while ((ent = (HEAP_STATS_ENTRY *) mht_get2 (heap_Bestspace->hfid_ht, hfid, NULL)) != NULL)
    {
      (void) mht_rem2 (heap_Bestspace->hfid_ht, &ent->hfid, ent, NULL, NULL);
      (void) mht_rem (heap_Bestspace->vpid_ht, &ent->best.vpid, NULL, NULL);
      (void) heap_stats_entry_free (thread_p, ent, NULL);
      ent = NULL;

      del_cnt++;
    }

  assert (del_cnt <= heap_Bestspace->num_stats_entries);

  heap_Bestspace->num_stats_entries -= del_cnt;

  assert (mht_count (heap_Bestspace->vpid_ht) == mht_count (heap_Bestspace->hfid_ht));
  pthread_mutex_unlock (&heap_Bestspace->bestspace_mutex);

  return del_cnt;
}

/*
 * heap_stats_del_bestspace_by_vpid () -
 *   return: NO_ERROR
 *
 *  vpid(in):
 */
static int
heap_stats_del_bestspace_by_vpid (THREAD_ENTRY * thread_p, VPID * vpid)
{
  HEAP_STATS_ENTRY *ent;
  int rc;

  rc = pthread_mutex_lock (&heap_Bestspace->bestspace_mutex);

  ent = (HEAP_STATS_ENTRY *) mht_get (heap_Bestspace->vpid_ht, vpid);
  if (ent == NULL)
    {
      goto end;
    }

  (void) mht_rem2 (heap_Bestspace->hfid_ht, &ent->hfid, ent, NULL, NULL);
  (void) mht_rem (heap_Bestspace->vpid_ht, &ent->best.vpid, NULL, NULL);
  (void) heap_stats_entry_free (thread_p, ent, NULL);
  ent = NULL;

  heap_Bestspace->num_stats_entries -= 1;

end:
  assert (mht_count (heap_Bestspace->vpid_ht) == mht_count (heap_Bestspace->hfid_ht));

  pthread_mutex_unlock (&heap_Bestspace->bestspace_mutex);

  return NO_ERROR;
}

/*
 * heap_stats_get_bestspace_by_vpid () -
 *   return: NO_ERROR
 *
 *  vpid(in):
 */
static HEAP_BESTSPACE
heap_stats_get_bestspace_by_vpid (THREAD_ENTRY * thread_p, VPID * vpid)
{
  HEAP_STATS_ENTRY *ent;
  HEAP_BESTSPACE best;
  int rc;

  best.freespace = -1;
  VPID_SET_NULL (&best.vpid);

  rc = pthread_mutex_lock (&heap_Bestspace->bestspace_mutex);

  ent = (HEAP_STATS_ENTRY *) mht_get (heap_Bestspace->vpid_ht, vpid);
  if (ent == NULL)
    {
      goto end;
    }

  best = ent->best;

end:
  assert (mht_count (heap_Bestspace->vpid_ht) == mht_count (heap_Bestspace->hfid_ht));

  pthread_mutex_unlock (&heap_Bestspace->bestspace_mutex);

  return best;
}

/*
 * Scan page buffer and latch page manipulation
 */

/*
 * heap_scan_pb_lock_and_fetch () -
 *   return:
 *   vpid_ptr(in):
 *   fetch_mode(in):
 *   lock(in):
 *   scan_cache(in):
 *
 * NOTE: Because this function is called in too many places and because it
 *   is useful where a page was fixed for debug purpose, we pass the
 *   caller file/line arguments to pgbuf_fix.
 */
#if defined (NDEBUG)
static PAGE_PTR
heap_scan_pb_lock_and_fetch (THREAD_ENTRY * thread_p, const VPID * vpid_ptr, PAGE_FETCH_MODE fetch_mode, LOCK lock,
                 HEAP_SCANCACHE * scan_cache, PGBUF_WATCHER * pg_watcher)
#else /* !NDEBUG */
static PAGE_PTR
heap_scan_pb_lock_and_fetch_debug (THREAD_ENTRY * thread_p, const VPID * vpid_ptr, PAGE_FETCH_MODE fetch_mode,
                   LOCK lock, HEAP_SCANCACHE * scan_cache, PGBUF_WATCHER * pg_watcher,
                   const char *caller_file, const int caller_line)
#endif              /* !NDEBUG */
{
  PAGE_PTR pgptr = NULL;
  LOCK page_lock;
  PGBUF_LATCH_MODE page_latch_mode;

  if (scan_cache != NULL)
    {
      if (scan_cache->page_latch == NULL_LOCK)
    {
      page_lock = NULL_LOCK;
    }
      else
    {
      assert (scan_cache->page_latch >= NULL_LOCK);
      assert (lock >= NULL_LOCK);
      page_lock = lock_Conv[scan_cache->page_latch][lock];
      assert (page_lock != NA_LOCK);
    }
    }
  else
    {
      page_lock = lock;
    }

  if (page_lock == S_LOCK)
    {
      page_latch_mode = PGBUF_LATCH_READ;
    }
  else
    {
      page_latch_mode = PGBUF_LATCH_WRITE;
    }

  if (pg_watcher != NULL)
    {
#if defined (NDEBUG)
      if (pgbuf_ordered_fix_release (thread_p, vpid_ptr, fetch_mode, page_latch_mode, pg_watcher) != NO_ERROR)
#else /* !NDEBUG */
      if (pgbuf_ordered_fix_debug (thread_p, vpid_ptr, fetch_mode, page_latch_mode, pg_watcher,
                   caller_file, caller_line) != NO_ERROR)
#endif /* !NDEBUG */
    {
      return NULL;
    }
      pgptr = pg_watcher->pgptr;
    }
  else
    {
#if defined (NDEBUG)
      pgptr = pgbuf_fix_release (thread_p, vpid_ptr, fetch_mode, page_latch_mode, PGBUF_UNCONDITIONAL_LATCH);
#else /* !NDEBUG */
      pgptr =
    pgbuf_fix_debug (thread_p, vpid_ptr, fetch_mode, page_latch_mode, PGBUF_UNCONDITIONAL_LATCH, caller_file,
             caller_line);
#endif /* !NDEBUG */
    }

  if (pgptr != NULL)
    {
      (void) pgbuf_check_page_ptype (thread_p, pgptr, PAGE_HEAP);
    }

  return pgptr;
}

/*
 * heap_is_big_length () -
 *   return: true/false
 *   length(in):
 */
bool
heap_is_big_length (int length)
{
  return (length > heap_Maxslotted_reclength) ? true : false;
}

/*
 * heap_get_spage_type () -
 *   return: the type of the slotted page of the heap file.
 */
static int
heap_get_spage_type (void)
{
  return ANCHORED_DONT_REUSE_SLOTS;
}

/*
 * heap_is_reusable_oid () -
 *   return: true if the heap file is reuse_oid table
 *   file_type(in): the file type of the heap file
 */
static bool
heap_is_reusable_oid (const FILE_TYPE file_type)
{
  if (file_type == FILE_HEAP)
    {
      return false;
    }
  else if (file_type == FILE_HEAP_REUSE_SLOTS)
    {
      return true;
    }
  else
    {
      assert (false);
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
    }
  return false;
}

/* TODO: STL::list for _cache.area */
/*
 * heap_classrepr_initialize_cache () - Initialize the class representation cache
 *   return: NO_ERROR
 */
static int
heap_classrepr_initialize_cache (void)
{
  HEAP_CLASSREPR_ENTRY *cache_entry;
  HEAP_CLASSREPR_LOCK *lock_entry;
  HEAP_CLASSREPR_HASH *hash_entry;
  int i, ret = NO_ERROR;
  size_t size;

  if (heap_Classrepr != NULL)
    {
      ret = heap_classrepr_finalize_cache ();
      if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }
    }

  /* initialize hash entries table */
  heap_Classrepr_cache.num_entries = HEAP_CLASSREPR_MAXCACHE;

  heap_Classrepr_cache.area =
    (HEAP_CLASSREPR_ENTRY *) malloc (sizeof (HEAP_CLASSREPR_ENTRY) * heap_Classrepr_cache.num_entries);
  if (heap_Classrepr_cache.area == NULL)
    {
      ret = ER_OUT_OF_VIRTUAL_MEMORY;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 1,
          sizeof (HEAP_CLASSREPR_ENTRY) * heap_Classrepr_cache.num_entries);
      goto exit_on_error;
    }

  cache_entry = heap_Classrepr_cache.area;
  for (i = 0; i < heap_Classrepr_cache.num_entries; i++)
    {
      pthread_mutex_init (&cache_entry[i].mutex, NULL);

      cache_entry[i].idx = i;
      cache_entry[i].fcnt = 0;
      cache_entry[i].zone = ZONE_FREE;
      cache_entry[i].next_wait_thrd = NULL;
      cache_entry[i].hash_next = NULL;
      cache_entry[i].prev = NULL;
      cache_entry[i].next = (i < heap_Classrepr_cache.num_entries - 1) ? &cache_entry[i + 1] : NULL;

      cache_entry[i].force_decache = false;

      OID_SET_NULL (&cache_entry[i].class_oid);
      cache_entry[i].max_reprid = DEFAULT_REPR_INCREMENT;
      cache_entry[i].repr = (OR_CLASSREP **) malloc (cache_entry[i].max_reprid * sizeof (OR_CLASSREP *));
      if (cache_entry[i].repr == NULL)
    {
      ret = ER_OUT_OF_VIRTUAL_MEMORY;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 1, cache_entry[i].max_reprid * sizeof (OR_CLASSREP *));
      goto exit_on_error;
    }
      memset (cache_entry[i].repr, 0, cache_entry[i].max_reprid * sizeof (OR_CLASSREP *));

      cache_entry[i].last_reprid = NULL_REPRID;
    }

  /* initialize hash bucket table */
  heap_Classrepr_cache.num_hash = CLASSREPR_HASH_SIZE;
  heap_Classrepr_cache.hash_table =
    (HEAP_CLASSREPR_HASH *) malloc (heap_Classrepr_cache.num_hash * sizeof (HEAP_CLASSREPR_HASH));
  if (heap_Classrepr_cache.hash_table == NULL)
    {
      ret = ER_OUT_OF_VIRTUAL_MEMORY;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 1, heap_Classrepr_cache.num_hash * sizeof (HEAP_CLASSREPR_HASH));
      goto exit_on_error;
    }

  hash_entry = heap_Classrepr_cache.hash_table;
  for (i = 0; i < heap_Classrepr_cache.num_hash; i++)
    {
      pthread_mutex_init (&hash_entry[i].hash_mutex, NULL);
      hash_entry[i].idx = i;
      hash_entry[i].hash_next = NULL;
      hash_entry[i].lock_next = NULL;
    }

  /* initialize hash lock table */
  size = thread_num_total_threads () * sizeof (HEAP_CLASSREPR_LOCK);
  heap_Classrepr_cache.lock_table = (HEAP_CLASSREPR_LOCK *) malloc (size);
  if (heap_Classrepr_cache.lock_table == NULL)
    {
      ret = ER_OUT_OF_VIRTUAL_MEMORY;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 1, size);
      goto exit_on_error;
    }
  lock_entry = heap_Classrepr_cache.lock_table;
  for (i = 0; i < (int) thread_num_total_threads (); i++)
    {
      OID_SET_NULL (&lock_entry[i].class_oid);
      lock_entry[i].lock_next = NULL;
      lock_entry[i].next_wait_thrd = NULL;
    }

  /* initialize LRU list */

  pthread_mutex_init (&heap_Classrepr_cache.LRU_list.LRU_mutex, NULL);
  heap_Classrepr_cache.LRU_list.LRU_top = NULL;
  heap_Classrepr_cache.LRU_list.LRU_bottom = NULL;

  /* initialize free list */
  pthread_mutex_init (&heap_Classrepr_cache.free_list.free_mutex, NULL);
  heap_Classrepr_cache.free_list.free_top = &heap_Classrepr_cache.area[0];
  heap_Classrepr_cache.free_list.free_cnt = heap_Classrepr_cache.num_entries;

  heap_Classrepr = &heap_Classrepr_cache;

  return ret;

exit_on_error:

  heap_Classrepr_cache.num_entries = 0;

  return (ret == NO_ERROR) ? ER_FAILED : ret;
}

/* TODO: STL::list for _cache.area */
/*
 * heap_classrepr_finalize_cache () - Destroy any cached structures
 *   return: NO_ERROR
 *
 * Note: Any cached representations are deallocated at this moment and
 * the hash table is also removed.
 */
static int
heap_classrepr_finalize_cache (void)
{
  HEAP_CLASSREPR_ENTRY *cache_entry;
  HEAP_CLASSREPR_HASH *hash_entry;
  int i, j;
  int ret = NO_ERROR;

  if (heap_Classrepr == NULL)
    {
      return NO_ERROR;      /* nop */
    }

#ifdef DEBUG_CLASSREPR_CACHE
  ret = heap_classrepr_dump_anyfixed ();
  if (ret != NO_ERROR)
    {
      return ret;
    }
#endif /* DEBUG_CLASSREPR_CACHE */

  /* finalize hash entries table */
  cache_entry = heap_Classrepr_cache.area;
  for (i = 0; cache_entry != NULL && i < heap_Classrepr_cache.num_entries; i++)
    {
      pthread_mutex_destroy (&cache_entry[i].mutex);

      if (cache_entry[i].repr == NULL)
    {
      assert (cache_entry[i].repr != NULL);
      continue;
    }

      for (j = 0; j <= cache_entry[i].last_reprid; j++)
    {
      if (cache_entry[i].repr[j] != NULL)
        {
          or_free_classrep (cache_entry[i].repr[j]);
          cache_entry[i].repr[j] = NULL;
        }
    }
      free_and_init (cache_entry[i].repr);
    }
  if (heap_Classrepr_cache.area != NULL)
    {
      free_and_init (heap_Classrepr_cache.area);
    }
  heap_Classrepr_cache.num_entries = -1;

  /* finalize hash bucket table */
  hash_entry = heap_Classrepr_cache.hash_table;
  for (i = 0; hash_entry != NULL && i < heap_Classrepr_cache.num_hash; i++)
    {
      pthread_mutex_destroy (&hash_entry[i].hash_mutex);
    }
  heap_Classrepr_cache.num_hash = -1;
  if (heap_Classrepr_cache.hash_table != NULL)
    {
      free_and_init (heap_Classrepr_cache.hash_table);
    }

  /* finalize hash lock table */
  if (heap_Classrepr_cache.lock_table != NULL)
    {
      free_and_init (heap_Classrepr_cache.lock_table);
    }

  /* finalize LRU list */

  pthread_mutex_destroy (&heap_Classrepr_cache.LRU_list.LRU_mutex);

  /* initialize free list */
  pthread_mutex_destroy (&heap_Classrepr_cache.free_list.free_mutex);

  heap_Classrepr = NULL;

  return ret;
}

/*
 * heap_classrepr_entry_reset () -
 *   return: NO_ERROR
 *   cache_entry(in):
 *
 * Note: Reset the given class representation entry.
 */
static int
heap_classrepr_entry_reset (HEAP_CLASSREPR_ENTRY * cache_entry)
{
  int i;
  int ret = NO_ERROR;

  if (cache_entry == NULL)
    {
      return NO_ERROR;      /* nop */
    }

  /* free all classrepr */
  for (i = 0; i <= cache_entry->last_reprid; i++)
    {
      if (cache_entry->repr[i] != NULL)
    {
      or_free_classrep (cache_entry->repr[i]);
      cache_entry->repr[i] = NULL;
    }
    }

  cache_entry->force_decache = false;
  OID_SET_NULL (&cache_entry->class_oid);
  if (cache_entry->max_reprid > DEFAULT_REPR_INCREMENT)
    {
      OR_CLASSREP **t;

      t = cache_entry->repr;
      cache_entry->repr = (OR_CLASSREP **) malloc (DEFAULT_REPR_INCREMENT * sizeof (OR_CLASSREP *));
      if (cache_entry->repr == NULL)
    {
      ret = ER_OUT_OF_VIRTUAL_MEMORY;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 1, DEFAULT_REPR_INCREMENT * sizeof (OR_CLASSREP *));
      cache_entry->repr = t;
    }
      else
    {
      free_and_init (t);
      cache_entry->max_reprid = DEFAULT_REPR_INCREMENT;
      memset (cache_entry->repr, 0, DEFAULT_REPR_INCREMENT * sizeof (OR_CLASSREP *));
    }

    }
  cache_entry->last_reprid = NULL_REPRID;

  return ret;
}

/*
 * heap_classrepr_entry_remove_from_LRU () -
 *   return: NO_ERROR
 *   cache_entry(in):
 */
static int
heap_classrepr_entry_remove_from_LRU (HEAP_CLASSREPR_ENTRY * cache_entry)
{
  if (cache_entry)
    {
      if (cache_entry == heap_Classrepr_cache.LRU_list.LRU_top)
    {
      heap_Classrepr_cache.LRU_list.LRU_top = cache_entry->next;
    }
      else
    {
      cache_entry->prev->next = cache_entry->next;
    }

      if (cache_entry == heap_Classrepr_cache.LRU_list.LRU_bottom)
    {
      heap_Classrepr_cache.LRU_list.LRU_bottom = cache_entry->prev;
    }
      else
    {
      cache_entry->next->prev = cache_entry->prev;
    }
    }

  return NO_ERROR;
}

/* TODO: STL::list for ->prev */
/*
 * heap_classrepr_decache_guessed_last () -
 *   return: NO_ERROR
 *   class_oid(in):
 *
 * Note: Decache the guessed last representations (i.e., that with -1)
 * from the given class.
 *
 * Note: This function should be called when a class is updated.
 *       1: During normal update
 */
static int
heap_classrepr_decache_guessed_last (const OID * class_oid)
{
  HEAP_CLASSREPR_ENTRY *cache_entry, *prev_entry, *cur_entry;
  HEAP_CLASSREPR_HASH *hash_anchor;
  int rv;
  int ret = NO_ERROR;

  if (class_oid != NULL)
    {
      hash_anchor = &heap_Classrepr->hash_table[REPR_HASH (class_oid)];

    search_begin:
      rv = pthread_mutex_lock (&hash_anchor->hash_mutex);

      for (cache_entry = hash_anchor->hash_next; cache_entry != NULL; cache_entry = cache_entry->hash_next)
    {
      if (OID_EQ (class_oid, &cache_entry->class_oid))
        {
          rv = pthread_mutex_trylock (&cache_entry->mutex);
          if (rv == 0)
        {
          goto delete_begin;
        }

          if (rv != EBUSY)
        {
          ret = ER_CSS_PTHREAD_MUTEX_LOCK;
          er_set_with_oserror (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 0);
          pthread_mutex_unlock (&hash_anchor->hash_mutex);
          goto exit_on_error;
        }

          pthread_mutex_unlock (&hash_anchor->hash_mutex);
          rv = pthread_mutex_lock (&cache_entry->mutex);

          /* cache_entry can be used by others. check again */
          if (!OID_EQ (class_oid, &cache_entry->class_oid))
        {
          pthread_mutex_unlock (&cache_entry->mutex);
          goto search_begin;
        }
          break;
        }
    }

      /* class_oid cache_entry is not found */
      if (cache_entry == NULL)
    {
      pthread_mutex_unlock (&hash_anchor->hash_mutex);
      goto exit_on_error;
    }

      /* hash anchor lock has been released */
      rv = pthread_mutex_lock (&hash_anchor->hash_mutex);

    delete_begin:

      /* delete classrepr from hash chain */
      prev_entry = NULL;
      cur_entry = hash_anchor->hash_next;
      while (cur_entry != NULL)
    {
      if (cur_entry == cache_entry)
        {
          break;
        }
      prev_entry = cur_entry;
      cur_entry = cur_entry->hash_next;
    }

      /* class_oid cache_entry is not found */
      if (cur_entry == NULL)
    {
      /* This cannot happen */
      pthread_mutex_unlock (&hash_anchor->hash_mutex);
      pthread_mutex_unlock (&cache_entry->mutex);

      goto exit_on_error;
    }

      if (prev_entry == NULL)
    {
      hash_anchor->hash_next = cur_entry->hash_next;
    }
      else
    {
      prev_entry->hash_next = cur_entry->hash_next;
    }
      cur_entry->hash_next = NULL;

      pthread_mutex_unlock (&hash_anchor->hash_mutex);

      cache_entry->force_decache = true;

      /* Remove from LRU list */
      if (cache_entry->zone == ZONE_LRU)
    {
      rv = pthread_mutex_lock (&heap_Classrepr_cache.LRU_list.LRU_mutex);
      (void) heap_classrepr_entry_remove_from_LRU (cache_entry);
      pthread_mutex_unlock (&heap_Classrepr_cache.LRU_list.LRU_mutex);
      cache_entry->zone = ZONE_VOID;
    }
      cache_entry->prev = NULL;
      cache_entry->next = NULL;

      if (cache_entry->fcnt == 0)
    {
      /* move cache_entry to free_list */
      ret = heap_classrepr_entry_reset (cache_entry);
      if (ret == NO_ERROR)
        {
          ret = heap_classrepr_entry_free (cache_entry);
        }
    }

      pthread_mutex_unlock (&cache_entry->mutex);
    }

  return ret;

exit_on_error:

  return (ret == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_classrepr_decache () - Deache any unfixed class representations of
 *                           given class
 *   return: NO_ERROR
 *   class_oid(in):
 *
 * Note: Decache all class representations of given class. If a class
 * is not given all class representations are decached.
 *
 * Note: This function should be called when a class is updated.
 *       1: At the end/beginning of rollback since we do not have any
 *          idea of a heap identifier of rolled back objects and we
 *          expend too much time, searching for the OID, every time we
 *          rolled back an updated object.
 */
int
heap_classrepr_decache (THREAD_ENTRY * thread_p, const OID * class_oid)
{
  int ret;

  ret = heap_classrepr_decache_guessed_last (class_oid);
  if (ret != NO_ERROR)
    {
      return ret;
    }

  if (csect_enter (thread_p, CSECT_HEAP_CHNGUESS, INF_WAIT) != NO_ERROR)
    {
      return ER_FAILED;
    }
  if (heap_Guesschn != NULL && heap_Guesschn->schema_change == false)
    {
      ret = heap_chnguess_decache (class_oid);
    }
  csect_exit (thread_p, CSECT_HEAP_CHNGUESS);

  return ret;
}

/* TODO: STL::list for _cache.area */
/*
 * heap_classrepr_free () - Free a class representation
 *   return: NO_ERROR
 *   classrep(in): The class representation structure
 *   idx_incache(in): An index if the desired class representation is part of
 *                    the cache, otherwise -1 (no part of cache)
 *
 * Note: Free a class representation. If the class representation was
 * part of the class representation cache, the fix count is
 * decremented and the class representation will continue be
 * cached. The representation entry will be subject for
 * replacement when the fix count is zero (no one is using it).
 * If the class representatin was not part of the cache, it is
 * freed.
 *
 * NOTE: consider to use heap_classrepr_free_and_init.
 */
int
heap_classrepr_free (OR_CLASSREP * classrep, int *idx_incache)
{
  HEAP_CLASSREPR_ENTRY *cache_entry;
  int rv;
  int ret = NO_ERROR;

  if (*idx_incache < 0)
    {
      or_free_classrep (classrep);
      return NO_ERROR;
    }

  cache_entry = &heap_Classrepr_cache.area[*idx_incache];

  rv = pthread_mutex_lock (&cache_entry->mutex);
  cache_entry->fcnt--;
  if (cache_entry->fcnt == 0)
    {
      /* 
       * Is this entry declared to be decached
       */
#ifdef DEBUG_CLASSREPR_CACHE
      rv = pthread_mutex_lock (&heap_Classrepr_cache.num_fix_entries_mutex);
      heap_Classrepr_cache.num_fix_entries--;
      pthread_mutex_unlock (&heap_Classrepr_cache.num_fix_entries_mutex);
#endif /* DEBUG_CLASSREPR_CACHE */
      if (cache_entry->force_decache != 0)
    {
      /* cache_entry is already removed from LRU list. */

      /* move cache_entry to free_list */
      ret = heap_classrepr_entry_free (cache_entry);
      if (ret == NO_ERROR)
        {
          ret = heap_classrepr_entry_reset (cache_entry);
        }
    }
      else
    {
      /* relocate entry to the top of LRU list */
      if (cache_entry != heap_Classrepr_cache.LRU_list.LRU_top)
        {
          rv = pthread_mutex_lock (&heap_Classrepr_cache.LRU_list.LRU_mutex);
          if (cache_entry->zone == ZONE_LRU)
        {
          /* remove from LRU list */
          (void) heap_classrepr_entry_remove_from_LRU (cache_entry);
        }

          /* insert into LRU top */
          cache_entry->prev = NULL;
          cache_entry->next = heap_Classrepr_cache.LRU_list.LRU_top;
          if (heap_Classrepr_cache.LRU_list.LRU_top == NULL)
        {
          heap_Classrepr_cache.LRU_list.LRU_bottom = cache_entry;
        }
          else
        {
          heap_Classrepr_cache.LRU_list.LRU_top->prev = cache_entry;
        }
          heap_Classrepr_cache.LRU_list.LRU_top = cache_entry;
          cache_entry->zone = ZONE_LRU;

          pthread_mutex_unlock (&heap_Classrepr_cache.LRU_list.LRU_mutex);
        }
    }
    }
  pthread_mutex_unlock (&cache_entry->mutex);
  *idx_incache = -1;

  return ret;
}

#ifdef SERVER_MODE

enum
{ NEED_TO_RETRY = 0, LOCK_ACQUIRED };

/*
 * heap_classrepr_lock_class () - Prevent other threads accessing class_oid
 *                              class representation.
 *   return: ER_FAILED, NEED_TO_RETRY or LOCK_ACQUIRED
 *   hash_anchor(in):
 *   class_oid(in):
 */
static int
heap_classrepr_lock_class (THREAD_ENTRY * thread_p, HEAP_CLASSREPR_HASH * hash_anchor, const OID * class_oid)
{
  HEAP_CLASSREPR_LOCK *cur_lock_entry;
  THREAD_ENTRY *cur_thrd_entry;

  if (thread_p == NULL)
    {
      thread_p = thread_get_thread_entry_info ();
      if (thread_p == NULL)
    {
      return ER_FAILED;
    }
    }
  cur_thrd_entry = thread_p;

  for (cur_lock_entry = hash_anchor->lock_next; cur_lock_entry != NULL; cur_lock_entry = cur_lock_entry->lock_next)
    {
      if (OID_EQ (&cur_lock_entry->class_oid, class_oid))
    {
      cur_thrd_entry->next_wait_thrd = cur_lock_entry->next_wait_thrd;
      cur_lock_entry->next_wait_thrd = cur_thrd_entry;

      thread_lock_entry (cur_thrd_entry);
      pthread_mutex_unlock (&hash_anchor->hash_mutex);
      thread_suspend_wakeup_and_unlock_entry (cur_thrd_entry, THREAD_HEAP_CLSREPR_SUSPENDED);

      if (cur_thrd_entry->resume_status == THREAD_HEAP_CLSREPR_RESUMED)
        {
          return NEED_TO_RETRY; /* traverse hash chain again */
        }
      else
        {
          /* probably due to an interrupt */
          assert ((cur_thrd_entry->resume_status == THREAD_RESUME_DUE_TO_INTERRUPT));
          return ER_FAILED;
        }
    }
    }

  cur_lock_entry = &heap_Classrepr_cache.lock_table[cur_thrd_entry->index];
  cur_lock_entry->class_oid = *class_oid;
  cur_lock_entry->next_wait_thrd = NULL;
  cur_lock_entry->lock_next = hash_anchor->lock_next;
  hash_anchor->lock_next = cur_lock_entry;

  pthread_mutex_unlock (&hash_anchor->hash_mutex);

  return LOCK_ACQUIRED;     /* lock acquired. */
}

/*
 * heap_classrepr_unlock_class () -
 *   return: NO_ERROR
 *   hash_anchor(in):
 *   class_oid(in):
 *   need_hash_mutex(in):
 */
static int
heap_classrepr_unlock_class (HEAP_CLASSREPR_HASH * hash_anchor, const OID * class_oid, int need_hash_mutex)
{
  HEAP_CLASSREPR_LOCK *prev_lock_entry, *cur_lock_entry;
  THREAD_ENTRY *cur_thrd_entry;
  int rv;

  /* if hash mutex lock is not acquired */
  if (need_hash_mutex)
    {
      rv = pthread_mutex_lock (&hash_anchor->hash_mutex);
    }

  prev_lock_entry = NULL;
  cur_lock_entry = hash_anchor->lock_next;
  while (cur_lock_entry != NULL)
    {
      if (OID_EQ (&cur_lock_entry->class_oid, class_oid))
    {
      break;
    }
      prev_lock_entry = cur_lock_entry;
      cur_lock_entry = cur_lock_entry->lock_next;
    }

  /* if lock entry is found, remove it from lock list */
  if (cur_lock_entry == NULL)
    {               /* this cannot happen */
      pthread_mutex_unlock (&hash_anchor->hash_mutex);
      return ER_FAILED;
    }

  if (prev_lock_entry == NULL)
    {
      hash_anchor->lock_next = cur_lock_entry->lock_next;
    }
  else
    {
      prev_lock_entry->lock_next = cur_lock_entry->lock_next;
    }
  cur_lock_entry->lock_next = NULL;
  pthread_mutex_unlock (&hash_anchor->hash_mutex);
  for (cur_thrd_entry = cur_lock_entry->next_wait_thrd; cur_thrd_entry != NULL;
       cur_thrd_entry = cur_lock_entry->next_wait_thrd)
    {
      cur_lock_entry->next_wait_thrd = cur_thrd_entry->next_wait_thrd;
      cur_thrd_entry->next_wait_thrd = NULL;

      thread_wakeup (cur_thrd_entry, THREAD_HEAP_CLSREPR_RESUMED);
    }

  return NO_ERROR;
}
#endif /* SERVER_MODE */

/* TODO: STL::list for ->prev */
/*
 * heap_classrepr_entry_alloc () -
 *   return:
 */
static HEAP_CLASSREPR_ENTRY *
heap_classrepr_entry_alloc (void)
{
  HEAP_CLASSREPR_HASH *hash_anchor;
  HEAP_CLASSREPR_ENTRY *cache_entry, *prev_entry, *cur_entry;
  int rv;

  cache_entry = NULL;

/* check_free_list: */

  /* 1. Get entry from free list */
  if (heap_Classrepr_cache.free_list.free_top == NULL)
    {
      goto check_LRU_list;
    }

  rv = pthread_mutex_lock (&heap_Classrepr_cache.free_list.free_mutex);
  if (heap_Classrepr_cache.free_list.free_top == NULL)
    {
      pthread_mutex_unlock (&heap_Classrepr_cache.free_list.free_mutex);
      cache_entry = NULL;
    }
  else
    {
      cache_entry = heap_Classrepr_cache.free_list.free_top;
      heap_Classrepr_cache.free_list.free_top = cache_entry->next;
      heap_Classrepr_cache.free_list.free_cnt--;
      pthread_mutex_unlock (&heap_Classrepr_cache.free_list.free_mutex);

      rv = pthread_mutex_lock (&cache_entry->mutex);
      cache_entry->next = NULL;
      cache_entry->zone = ZONE_VOID;

      return cache_entry;
    }

check_LRU_list:
  /* 2. Get entry from LRU list */
  if (heap_Classrepr_cache.LRU_list.LRU_bottom == NULL)
    {
      goto expand_list;
    }

  rv = pthread_mutex_lock (&heap_Classrepr_cache.LRU_list.LRU_mutex);
  for (cache_entry = heap_Classrepr_cache.LRU_list.LRU_bottom; cache_entry != NULL; cache_entry = cache_entry->prev)
    {
      if (cache_entry->fcnt == 0)
    {
      /* remove from LRU list */
      (void) heap_classrepr_entry_remove_from_LRU (cache_entry);
      cache_entry->zone = ZONE_VOID;
      cache_entry->next = cache_entry->prev = NULL;
      break;
    }
    }
  pthread_mutex_unlock (&heap_Classrepr_cache.LRU_list.LRU_mutex);

  if (cache_entry == NULL)
    {
      goto expand_list;
    }

  rv = pthread_mutex_lock (&cache_entry->mutex);
  /* if some has referenced, retry */
  if (cache_entry->fcnt != 0)
    {
      pthread_mutex_unlock (&cache_entry->mutex);
      goto check_LRU_list;
    }

  /* delete classrepr from hash chain */
  hash_anchor = &heap_Classrepr->hash_table[REPR_HASH (&cache_entry->class_oid)];
  rv = pthread_mutex_lock (&hash_anchor->hash_mutex);
  prev_entry = NULL;
  cur_entry = hash_anchor->hash_next;
  while (cur_entry != NULL)
    {
      if (cur_entry == cache_entry)
    {
      break;
    }
      prev_entry = cur_entry;
      cur_entry = cur_entry->hash_next;
    }

  if (cur_entry == NULL)
    {
      /* This cannot happen */
      pthread_mutex_unlock (&hash_anchor->hash_mutex);
      pthread_mutex_unlock (&cache_entry->mutex);

      return NULL;
    }
  if (prev_entry == NULL)
    {
      hash_anchor->hash_next = cur_entry->hash_next;
    }
  else
    {
      prev_entry->hash_next = cur_entry->hash_next;
    }
  cur_entry->hash_next = NULL;
  pthread_mutex_unlock (&hash_anchor->hash_mutex);

  (void) heap_classrepr_entry_reset (cache_entry);

end:

  return cache_entry;

expand_list:

  /* not supported */
  cache_entry = NULL;
  goto end;
}

/* TODO: STL::list for ->next */
/*
 * heap_classrepr_entry_free () -
 *   return: NO_ERROR
 *   cache_entry(in):
 */
static int
heap_classrepr_entry_free (HEAP_CLASSREPR_ENTRY * cache_entry)
{
  int rv;
  rv = pthread_mutex_lock (&heap_Classrepr_cache.free_list.free_mutex);

  cache_entry->next = heap_Classrepr_cache.free_list.free_top;
  heap_Classrepr_cache.free_list.free_top = cache_entry;
  cache_entry->zone = ZONE_FREE;
  heap_Classrepr_cache.free_list.free_cnt++;

  pthread_mutex_unlock (&heap_Classrepr_cache.free_list.free_mutex);

  return NO_ERROR;
}

/*
 * heap_classrepr_get_from_record ()
 *   return: classrepr
 *
 *   last_reprid(out):
 *   class_oid(in): The class identifier
 *   class_recdes(in): The class recdes (when know) or NULL
 *   reprid(in): Representation of the class or NULL_REPRID for last one
 */
static OR_CLASSREP *
heap_classrepr_get_from_record (THREAD_ENTRY * thread_p, REPR_ID * last_reprid, const OID * class_oid,
                RECDES * class_recdes, REPR_ID reprid)
{
  RECDES peek_recdes;
  RECDES *recdes = NULL;
  HEAP_SCANCACHE scan_cache;
  OR_CLASSREP *repr = NULL;

  if (last_reprid != NULL)
    {
      *last_reprid = NULL_REPRID;
    }

  if (class_recdes != NULL)
    {
      recdes = class_recdes;
    }
  else
    {
      heap_scancache_quick_start_root_hfid (thread_p, &scan_cache);
      if (heap_get_class_record (thread_p, class_oid, &peek_recdes, &scan_cache, PEEK) != S_SUCCESS)
    {
      goto end;
    }
      recdes = &peek_recdes;
    }

  repr = or_get_classrep (recdes, reprid);
  if (last_reprid != NULL)
    {
      *last_reprid = or_rep_id (recdes);
    }

end:
  if (class_recdes == NULL)
    {
      heap_scancache_end (thread_p, &scan_cache);
    }
  return repr;
}

/*
 * heap_classrepr_get () - Obtain the desired class representation
 *   return: classrepr
 *   class_oid(in): The class identifier
 *   class_recdes(in): The class recdes (when know) or NULL
 *   reprid(in): Representation of the class or NULL_REPRID for last one
 *   idx_incache(in): An index if the desired class representation is part
 *                    of the cache
 *
 * Note: Obtain the desired class representation for the given class.
 */
OR_CLASSREP *
heap_classrepr_get (THREAD_ENTRY * thread_p, const OID * class_oid, RECDES * class_recdes, REPR_ID reprid,
            int *idx_incache)
{
  HEAP_CLASSREPR_ENTRY *cache_entry;
  HEAP_CLASSREPR_HASH *hash_anchor;
  OR_CLASSREP *repr = NULL;
  OR_CLASSREP *repr_from_record = NULL;
  OR_CLASSREP *repr_last = NULL;
  REPR_ID last_reprid;
  int r;

  *idx_incache = -1;

  hash_anchor = &heap_Classrepr->hash_table[REPR_HASH (class_oid)];

  /* search entry with class_oid from hash chain */
search_begin:
  r = pthread_mutex_lock (&hash_anchor->hash_mutex);

  for (cache_entry = hash_anchor->hash_next; cache_entry != NULL; cache_entry = cache_entry->hash_next)
    {
      if (OID_EQ (class_oid, &cache_entry->class_oid))
    {
      r = pthread_mutex_trylock (&cache_entry->mutex);
      if (r == 0)
        {
          pthread_mutex_unlock (&hash_anchor->hash_mutex);
        }
      else
        {
          if (r != EBUSY)
        {
          /* some error code */
          er_set_with_oserror (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_CSS_PTHREAD_MUTEX_LOCK, 0);
          pthread_mutex_unlock (&hash_anchor->hash_mutex);
          goto exit;
        }
          /* if cache_entry lock is busy. release hash mutex lock and lock cache_entry lock unconditionally */
          pthread_mutex_unlock (&hash_anchor->hash_mutex);
          r = pthread_mutex_lock (&cache_entry->mutex);
        }
      /* check if cache_entry is used by others */
      if (!OID_EQ (class_oid, &cache_entry->class_oid))
        {
          pthread_mutex_unlock (&cache_entry->mutex);
          goto search_begin;
        }

      break;
    }
    }

  if (cache_entry == NULL)
    {
      if (repr_from_record == NULL)
    {
      /* note: we need to read class record from heap page. however, latching a page and holding mutex is never a
       *       good idea, and it can generate ugly deadlocks. but in most cases, we won't have concurrency here,
       *       so let's try a conditional latch on page of class. if that doesn't work, release the hash mutex,
       *       read representation from heap and restart the process to ensure consistency. */
      VPID vpid_of_class;
      PAGE_PTR page_of_class = NULL;
      VPID_GET_FROM_OID (&vpid_of_class, class_oid);
      page_of_class = pgbuf_fix (thread_p, &vpid_of_class, OLD_PAGE, PGBUF_LATCH_READ, PGBUF_CONDITIONAL_LATCH);
      if (page_of_class == NULL)
        {
          /* we cannot hold mutex */
          pthread_mutex_unlock (&hash_anchor->hash_mutex);
        }
      else if (spage_get_record_type (page_of_class, class_oid->slotid) != REC_HOME)
        {
          /* things get too complicated when we need to do ordered fix. */
          pgbuf_unfix_and_init (thread_p, page_of_class);
          pthread_mutex_unlock (&hash_anchor->hash_mutex);
        }
      repr_from_record = heap_classrepr_get_from_record (thread_p, &last_reprid, class_oid, class_recdes, reprid);
      if (repr_from_record == NULL)
        {
          ASSERT_ERROR ();

          if (page_of_class != NULL)
        {
          pthread_mutex_unlock (&hash_anchor->hash_mutex);
          pgbuf_unfix_and_init (thread_p, page_of_class);
        }
          goto exit;
        }
      if (reprid == NULL_REPRID)
        {
          reprid = last_reprid;
        }
      if (reprid != last_reprid && repr_last == NULL)
        {
          repr_last = heap_classrepr_get_from_record (thread_p, &last_reprid, class_oid, class_recdes, last_reprid);
          if (repr_last == NULL)
        {
          /* can we accept this case? */
        }
        }
      if (page_of_class == NULL)
        {
          /* hash mutex was released, we need to restart search. */
          goto search_begin;
        }
      else
        {
          pgbuf_unfix_and_init (thread_p, page_of_class);
          /* hash mutex was kept */
          /* fall through */
        }
    }
      assert (repr_from_record != NULL);
      assert (last_reprid != NULL_REPRID);

#ifdef SERVER_MODE
      /* class_oid was not found. Lock class_oid. heap_classrepr_lock_class () release hash_anchor->hash_lock */
      r = heap_classrepr_lock_class (thread_p, hash_anchor, class_oid);
      if (r != LOCK_ACQUIRED)
    {
      if (r == NEED_TO_RETRY)
        {
          goto search_begin;
        }
      else
        {
          assert (r == ER_FAILED);
          goto exit;
        }
    }
#endif

      /* Get free entry */
      cache_entry = heap_classrepr_entry_alloc ();
      if (cache_entry == NULL)
    {
      /* if all cache entry is busy, return disk repr. */

#ifdef SERVER_MODE
      /* free lock for class_oid */
      (void) heap_classrepr_unlock_class (hash_anchor, class_oid, true);
#endif

      if (repr_last != NULL)
        {
          or_free_classrep (repr_last);
        }

      /* return disk repr when repr cache is full */
      return repr_from_record;
    }

      /* check if cache_entry->repr[last_reprid] is valid. */
      if (last_reprid >= cache_entry->max_reprid)
    {
      free_and_init (cache_entry->repr);

      cache_entry->repr = (OR_CLASSREP **) malloc ((last_reprid + 1) * sizeof (OR_CLASSREP *));
      if (cache_entry->repr == NULL)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1,
              (last_reprid + 1) * sizeof (OR_CLASSREP *));

          pthread_mutex_unlock (&cache_entry->mutex);
          (void) heap_classrepr_entry_free (cache_entry);
#ifdef SERVER_MODE
          (void) heap_classrepr_unlock_class (hash_anchor, class_oid, true);
#endif
          if (repr != NULL)
        {
          or_free_classrep (repr);
          repr = NULL;
        }
          goto exit;
        }
      cache_entry->max_reprid = last_reprid + 1;

      memset (cache_entry->repr, 0, cache_entry->max_reprid * sizeof (OR_CLASSREP *));
    }

      if (reprid <= NULL_REPRID || reprid > last_reprid || reprid > cache_entry->max_reprid)
    {
      assert (false);

      pthread_mutex_unlock (&cache_entry->mutex);
      (void) heap_classrepr_entry_free (cache_entry);
#ifdef SERVER_MODE
      (void) heap_classrepr_unlock_class (hash_anchor, class_oid, true);
#endif

      if (repr != NULL)
        {
          or_free_classrep (repr);
          repr = NULL;
        }

      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_CT_UNKNOWN_REPRID, 1, reprid);
      goto exit;
    }

      cache_entry->repr[reprid] = repr_from_record;
      repr = cache_entry->repr[reprid];
      repr_from_record = NULL;
      cache_entry->last_reprid = last_reprid;
      if (reprid != last_reprid)
    {           /* if last repr is not cached */
      /* normally, we should not access heap record while keeping mutex in cache entry. however, this entry was not
       * yet attached to cache, so no one will get its mutex yet */
      cache_entry->repr[last_reprid] = repr_last;
      repr_last = NULL;
    }

      cache_entry->fcnt = 1;
      cache_entry->class_oid = *class_oid;
#ifdef DEBUG_CLASSREPR_CACHE
      r = pthread_mutex_lock (&heap_Classrepr_cache.num_fix_entries_mutex);
      heap_Classrepr_cache.num_fix_entries++;
      pthread_mutex_unlock (&heap_Classrepr_cache.num_fix_entries_mutex);

#endif /* DEBUG_CLASSREPR_CACHE */
      *idx_incache = cache_entry->idx;

      /* Add to hash chain, and remove lock for class_oid */
      r = pthread_mutex_lock (&hash_anchor->hash_mutex);
      cache_entry->hash_next = hash_anchor->hash_next;
      hash_anchor->hash_next = cache_entry;

#ifdef SERVER_MODE
      (void) heap_classrepr_unlock_class (hash_anchor, class_oid, false);
#endif
    }
  else
    {
      /* now, we have already cache_entry for class_oid. if it contains repr info for reprid, return it. else load
       * classrepr info for it */

      if (reprid == NULL_REPRID)
    {
      reprid = cache_entry->last_reprid;
    }

      if (reprid <= NULL_REPRID || reprid > cache_entry->last_reprid || reprid > cache_entry->max_reprid)
    {
      assert (false);

      pthread_mutex_unlock (&cache_entry->mutex);

      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_CT_UNKNOWN_REPRID, 1, reprid);
      goto exit;
    }

      /* reprid cannot be greater than cache_entry->last_reprid. */
      repr = cache_entry->repr[reprid];
      if (repr == NULL)
    {
      /* load repr. info. for reprid of class_oid */
      if (repr_from_record == NULL)
        {
          /* we need to read record from its page. we cannot hold cache mutex and latch a page. */
          pthread_mutex_unlock (&cache_entry->mutex);
          repr_from_record =
        heap_classrepr_get_from_record (thread_p, &last_reprid, class_oid, class_recdes, reprid);
          if (repr_from_record == NULL)
        {
          goto exit;
        }
          /* we need to start over */
          goto search_begin;
        }
      else
        {
          /* use load representation from record */
          cache_entry->repr[reprid] = repr_from_record;
          repr = repr_from_record;
          repr_from_record = NULL;

          /* fall through */
        }
    }

      cache_entry->fcnt++;
      *idx_incache = cache_entry->idx;
    }
  pthread_mutex_unlock (&cache_entry->mutex);

exit:
  if (repr_from_record != NULL)
    {
      or_free_classrep (repr_from_record);
    }
  if (repr_last != NULL)
    {
      or_free_classrep (repr_last);
    }
  return repr;
}

#ifdef DEBUG_CLASSREPR_CACHE
/*
 * heap_classrepr_dump_cache () - Dump the class representation cache
 *   return: NO_ERROR
 *   simple_dump(in):
 *
 * Note: Dump the class representation cache.
 */
static int
heap_classrepr_dump_cache (bool simple_dump)
{
  OR_CLASSREP *classrepr;
  HEAP_CLASSREPR_ENTRY *cache_entry;
  int i, j;
  int rv;
  int ret = NO_ERROR;

  if (heap_Classrepr == NULL)
    {
      return NO_ERROR;      /* nop */
    }

  (void) fflush (stderr);
  (void) fflush (stdout);

  fprintf (stdout, "*** Class Representation cache dump *** \n");
  fprintf (stdout, " Number of entries = %d, Number of used entries = %d\n", heap_Classrepr->num_entries,
       heap_Classrepr->num_entries - heap_Classrepr->free_list.free_cnt);

  for (cache_entry = heap_Classrepr->area, i = 0; i < heap_Classrepr->num_entries; cache_entry++, i++)
    {
      fprintf (stdout, " \nEntry_id %d\n", cache_entry->idx);

      rv = pthread_mutex_lock (&cache_entry->mutex);
      for (j = 0; j <= cache_entry->last_reprid; j++)
    {
      classrepr = cache_entry->repr[j];
      if (classrepr == NULL)
        {
          fprintf (stdout, ".....\n");
          continue;
        }
      fprintf (stdout, " Fix count = %d, force_decache = %d\n", cache_entry->fcnt, cache_entry->force_decache);

      if (simple_dump == true)
        {
          fprintf (stdout, " Class_oid = %d|%d|%d, Reprid = %d\n", (int) cache_entry->class_oid.volid,
               cache_entry->class_oid.pageid, (int) cache_entry->class_oid.slotid, cache_entry->repr[j]->id);
          fprintf (stdout, " Representation address = %p\n", classrepr);

        }
      else
        {
          ret = heap_classrepr_dump (&cache_entry->class_oid, classrepr);
        }
    }

      pthread_mutex_unlock (&cache_entry->mutex);
    }

  return ret;
}
#endif /* DEBUG_CLASSREPR_CACHE */

/*
 * heap_classrepr_dump () - Dump schema of a given class representation
 *   return: NO_ERROR
 *   class_oid(in):
 *   repr(in): The class representation
 *
 * Note: Dump the class representation cache.
 */
static int
heap_classrepr_dump (THREAD_ENTRY * thread_p, FILE * fp, const OID * class_oid, const OR_CLASSREP * repr)
{
  OR_ATTRIBUTE *volatile attrepr;
  volatile int i;
  int k, j;
  char *classname;
  const char *attr_name;
  DB_VALUE def_dbvalue;
  PR_TYPE *pr_type;
  int disk_length;
  OR_BUF buf;
  bool copy;
  RECDES recdes = RECDES_INITIALIZER;   /* Used to obtain attrnames */
  int ret = NO_ERROR;
  char *index_name = NULL;
  char *string = NULL;
  int alloced_string = 0;
  HEAP_SCANCACHE scan_cache;

  /* 
   * The class is fetched to print the attribute names.
   *
   * This is needed since the name of the attributes is not contained
   * in the class representation structure.
   */
  (void) heap_scancache_quick_start_root_hfid (thread_p, &scan_cache);

  if (repr == NULL)
    {
      goto exit_on_error;
    }

  if (heap_get_class_record (thread_p, class_oid, &recdes, &scan_cache, COPY) != S_SUCCESS)
    {
      goto exit_on_error;
    }

  classname = or_class_name (&recdes);
  assert (classname != NULL);

  fprintf (fp, "\n");
  fprintf (fp,
       " Class-OID = %d|%d|%d, Classname = %s, reprid = %d,\n"
       " Attrs: Tot = %d, Nfix = %d, Nvar = %d, Nshare = %d, Nclass = %d,\n Total_length_of_fixattrs = %d\n",
       (int) class_oid->volid, class_oid->pageid, (int) class_oid->slotid, classname, repr->id, repr->n_attributes,
       (repr->n_attributes - repr->n_variable - repr->n_shared_attrs - repr->n_class_attrs), repr->n_variable,
       repr->n_shared_attrs, repr->n_class_attrs, repr->fixed_length);

  if (repr->n_attributes > 0)
    {
      fprintf (fp, "\n");
      fprintf (fp, " Attribute Specifications:\n");
    }

  for (i = 0, attrepr = repr->attributes; i < repr->n_attributes; i++, attrepr++)
    {
      string = NULL;
      alloced_string = 0;
      ret = or_get_attrname (&recdes, attrepr->id, &string, &alloced_string);
      if (ret != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit_on_error;
    }

      attr_name = string;
      if (attr_name == NULL)
    {
      attr_name = "?????";
    }

      fprintf (fp, "\n Attrid = %d, Attrname = %s, type = %s,\n location = %d, position = %d,\n", attrepr->id,
           attr_name, pr_type_name (attrepr->type), attrepr->location, attrepr->position);

      if (string != NULL && alloced_string == 1)
    {
      db_private_free_and_init (thread_p, string);
    }

      if (!OID_ISNULL (&attrepr->classoid) && !OID_EQ (&attrepr->classoid, class_oid))
    {
      if (heap_get_class_name (thread_p, &attrepr->classoid, &classname) != NO_ERROR || classname == NULL)
        {
          ASSERT_ERROR_AND_SET (ret);
          goto exit_on_error;
        }
      fprintf (fp, " Inherited from Class: oid = %d|%d|%d, Name = %s\n", (int) attrepr->classoid.volid,
           attrepr->classoid.pageid, (int) attrepr->classoid.slotid, classname);
      free_and_init (classname);
    }

      if (attrepr->n_btids > 0)
    {
      fprintf (fp, " Number of Btids = %d,\n", attrepr->n_btids);
      for (k = 0; k < attrepr->n_btids; k++)
        {
          index_name = NULL;
          /* find index_name */
          for (j = 0; j < repr->n_indexes; ++j)
        {
          if (BTID_IS_EQUAL (&(repr->indexes[j].btid), &(attrepr->btids[k])))
            {
              index_name = repr->indexes[j].btname;
              break;
            }
        }

          fprintf (fp, " BTID: VFID %d|%d, Root_PGID %d, %s\n", (int) attrepr->btids[k].vfid.volid,
               attrepr->btids[k].vfid.fileid, attrepr->btids[k].root_pageid,
               (index_name == NULL) ? "unknown" : index_name);
        }
    }

      /* 
       * Dump the default value if any.
       */
      fprintf (fp, " Default disk value format:\n");
      fprintf (fp, "   length = %d, value = ", attrepr->default_value.val_length);

      if (attrepr->default_value.val_length <= 0)
    {
      fprintf (fp, "NULL");
    }
      else
    {
      or_init (&buf, (char *) attrepr->default_value.value, attrepr->default_value.val_length);
      buf.error_abort = 1;

      switch (_setjmp (buf.env))
        {
        case 0:
          /* Do not copy the string--just use the pointer.  The pr_ routines for strings and sets have different
           * semantics for length. A negative length value for strings means "don't copy the string, just use the
           * pointer". */

          disk_length = attrepr->default_value.val_length;
          copy = (pr_is_set_type (attrepr->type)) ? true : false;
          pr_type = PR_TYPE_FROM_ID (attrepr->type);
          if (pr_type)
        {
          (*(pr_type->data_readval)) (&buf, &def_dbvalue, attrepr->domain, disk_length, copy, NULL, 0);

          db_value_fprint (stdout, &def_dbvalue);
          (void) pr_clear_value (&def_dbvalue);
        }
          else
        {
          fprintf (fp, "PR_TYPE is NULL");
        }
          break;
        default:
          /* 
           * An error was found during the reading of the attribute value
           */
          fprintf (fp, "Error transforming the default value\n");
          break;
        }
    }
      fprintf (fp, "\n");
    }

  (void) heap_scancache_end (thread_p, &scan_cache);

  return ret;

exit_on_error:

  (void) heap_scancache_end (thread_p, &scan_cache);

  fprintf (fp, "Dump has been aborted...");

  return (ret == NO_ERROR) ? ER_FAILED : ret;
}

#ifdef DEBUG_CLASSREPR_CACHE
/*
 * heap_classrepr_dump_anyfixed() - Dump class representation cache if
 *                                   any entry is fixed
 *   return: NO_ERROR
 *
 * Note: The class representation cache is dumped if any cache entry is fixed
 *
 * This is a debugging function that can be used to verify if
 * entries were freed after a set of operations (e.g., a
 * transaction or a API function).
 *
 * Note:
 * This function will not give you good results when there are
 * multiple users in the system (multiprocessing). However, it
 * can be used during shuttdown.
 */
int
heap_classrepr_dump_anyfixed (void)
{
  int ret = NO_ERROR;

  if (heap_Classrepr->num_fix_entries > 0)
    {
      er_log_debug (ARG_FILE_LINE, "heap_classrepr_dump_anyfixed: Some entries are fixed\n");
      ret = heap_classrepr_dump_cache (true);
    }

  return ret;
}
#endif /* DEBUG_CLASSREPR_CACHE */

/*
 * heap_stats_get_min_freespace () - Minimal space to consider a page for statistics
 *   return: int minspace
 *   heap_hdr(in): Current header of heap
 *
 * Note: Find the minimal space to consider to continue caching a page
 * for statistics.
 */
static int
heap_stats_get_min_freespace (HEAP_HDR_STATS * heap_hdr)
{
  int min_freespace;
  int header_size;

  header_size = OR_MVCC_MAX_HEADER_SIZE;

  /* 
   * Don't cache as a good space page if page does not have at least
   * unfill_space + one record
   */

  if (heap_hdr->estimates.num_recs > 0)
    {
      min_freespace = (int) (heap_hdr->estimates.recs_sumlen / heap_hdr->estimates.num_recs);

      if (min_freespace < (header_size + 20))
    {
      min_freespace = header_size + 20; /* Assume very small records */
    }
    }
  else
    {
      min_freespace = header_size + 20; /* Assume very small records */
    }

  min_freespace += heap_hdr->unfill_space;

  min_freespace = MIN (min_freespace, HEAP_DROP_FREE_SPACE);

  return min_freespace;
}

/*
 * heap_stats_update () - Update one header hinted page space statistics
 *   return: NO_ERROR
 *   pgptr(in): Page pointer
 *   hfid(in): Object heap file identifier
 *   prev_freespace(in):
 *
 * NOTE: There should be at least HEAP_DROP_FREE_SPACE in order to
 *       insert this page to best hint array.
 *       If we cannot fix a heap header page due to holding it by
 *       others, we will postpone this updating until next deletion.
 *       In this case, unfortunately, if some record is not deleted
 *       from this page in the future, we may not use this page until
 *       heap_stats_sync_bestspace function searches all pages.
 */
void
heap_stats_update (THREAD_ENTRY * thread_p, PAGE_PTR pgptr, const HFID * hfid, int prev_freespace)
{
  VPID *vpid;
  int freespace, error;
  bool need_update;

  freespace = spage_get_free_space_without_saving (thread_p, pgptr, &need_update);
  if (prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES) > 0)
    {
      if (prev_freespace < freespace)
    {
      vpid = pgbuf_get_vpid_ptr (pgptr);
      assert_release (vpid != NULL);

      (void) heap_stats_add_bestspace (thread_p, hfid, vpid, freespace);
    }
    }

  if (need_update || prev_freespace <= HEAP_DROP_FREE_SPACE)
    {
      if (freespace > HEAP_DROP_FREE_SPACE)
    {
      vpid = pgbuf_get_vpid_ptr (pgptr);
      assert_release (vpid != NULL);

      error = heap_stats_update_internal (thread_p, hfid, vpid, freespace);
      if (error != NO_ERROR)
        {
          spage_set_need_update_best_hint (thread_p, pgptr, true);
        }
      else if (need_update == true)
        {
          spage_set_need_update_best_hint (thread_p, pgptr, false);
        }
    }
      else if (need_update == true)
    {
      spage_set_need_update_best_hint (thread_p, pgptr, false);
    }
    }
}

/*
 * heap_stats_update_internal () - Update one header hinted page space statistics
 *   return: NO_ERROR
 *   hfid(in): Object heap file identifier
 *   lotspace_vpid(in): Page which has a lot of free space
 *   free_space(in): The free space on the page
 *
 * Note: Update header hinted best space page information. This
 * function is used during deletions and updates when the free
 * space on the page is greater than HEAP_DROP_FREE_SPACE.
 */
static int
heap_stats_update_internal (THREAD_ENTRY * thread_p, const HFID * hfid, VPID * lotspace_vpid, int free_space)
{
  HEAP_HDR_STATS *heap_hdr; /* Header of heap structure */
  PAGE_PTR hdr_pgptr = NULL;    /* Page pointer to header page */
  VPID vpid;            /* Page-volume identifier */
  RECDES recdes;        /* Header record descriptor */
  LOG_DATA_ADDR addr;       /* Address of logging data */
  int i, best;
  int ret = NO_ERROR;

  /* Retrieve the header of heap */
  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;

  /* 
   * We do not want to wait for the following operation.
   * So, if we cannot lock the page return.
   */
  hdr_pgptr = pgbuf_fix (thread_p, &vpid, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_CONDITIONAL_LATCH);
  if (hdr_pgptr == NULL)
    {
      /* Page is busy or other type of error */
      goto exit_on_error;
    }

  (void) pgbuf_check_page_ptype (thread_p, hdr_pgptr, PAGE_HEAP);

  /* 
   * Peek the header record to find statistics for insertion.
   * Update the statistics directly.
   */
  if (spage_get_record (thread_p, hdr_pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      goto exit_on_error;
    }

  heap_hdr = (HEAP_HDR_STATS *) recdes.data;
  best = heap_hdr->estimates.head;

  if (free_space >= heap_stats_get_min_freespace (heap_hdr))
    {
      /* 
       * We do not compare with the current stored values since these values
       * may not be accurate at all. When the given one is supposed to be
       * accurate.
       */

      /* 
       * Find a good place to insert this page
       */
      for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      if (VPID_ISNULL (&heap_hdr->estimates.best[best].vpid)
          || heap_hdr->estimates.best[best].freespace <= HEAP_DROP_FREE_SPACE)
        {
          break;
        }

      best = HEAP_STATS_NEXT_BEST_INDEX (best);
    }

      if (VPID_ISNULL (&heap_hdr->estimates.best[best].vpid))
    {
      heap_hdr->estimates.num_high_best++;
      assert (heap_hdr->estimates.num_high_best <= HEAP_NUM_BEST_SPACESTATS);
    }
      else if (heap_hdr->estimates.best[best].freespace > HEAP_DROP_FREE_SPACE)
    {
      heap_hdr->estimates.num_other_high_best++;

      heap_stats_put_second_best (heap_hdr, &heap_hdr->estimates.best[best].vpid);
    }
      /* 
       * Now substitute the entry with the new information
       */

      heap_hdr->estimates.best[best].freespace = free_space;
      heap_hdr->estimates.best[best].vpid = *lotspace_vpid;

      heap_hdr->estimates.head = HEAP_STATS_NEXT_BEST_INDEX (best);

      /* 
       * The changes to the statistics are not logged. They are fixed
       * automatically sooner or later
       */

      addr.vfid = &hfid->vfid;
      addr.pgptr = hdr_pgptr;
      addr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;
      log_skip_logging (thread_p, &addr);
      pgbuf_set_dirty (thread_p, hdr_pgptr, FREE);
      hdr_pgptr = NULL;
    }
  else
    {
      pgbuf_unfix_and_init (thread_p, hdr_pgptr);
    }

  return ret;

exit_on_error:
  if (hdr_pgptr)
    {
      pgbuf_unfix_and_init (thread_p, hdr_pgptr);
    }

  return (ret == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_stats_put_second_best () - Put a free page into second best hint array
 *   return: void
 *   heap_hdr(in): Statistics of heap file
 *   vpid(in): VPID to be added
 *
 * NOTE: A free page is not always inserted to the second best hint array.
 *       Second best hints will be collected for every 1000 pages in order
 *       to increase randomness for "emptying contiguous pages" scenario.
 */
static void
heap_stats_put_second_best (HEAP_HDR_STATS * heap_hdr, VPID * vpid)
{
  int tail;

  if (heap_hdr->estimates.num_substitutions++ % 1000 == 0)
    {
      tail = heap_hdr->estimates.tail_second_best;

      heap_hdr->estimates.second_best[tail] = *vpid;
      heap_hdr->estimates.tail_second_best = HEAP_STATS_NEXT_BEST_INDEX (tail);

      if (heap_hdr->estimates.num_second_best == HEAP_NUM_BEST_SPACESTATS)
    {
      assert (heap_hdr->estimates.head_second_best == tail);
      heap_hdr->estimates.head_second_best = heap_hdr->estimates.tail_second_best;
    }
      else
    {
      assert (heap_hdr->estimates.num_second_best < HEAP_NUM_BEST_SPACESTATS);
      heap_hdr->estimates.num_second_best++;
    }

      /* If both head and tail refer to the same index, the number of second best hints is
       * HEAP_NUM_BEST_SPACESTATS(10). */
      assert (heap_hdr->estimates.num_second_best != 0);
      assert ((heap_hdr->estimates.tail_second_best > heap_hdr->estimates.head_second_best)
          ? ((heap_hdr->estimates.tail_second_best - heap_hdr->estimates.head_second_best)
         == heap_hdr->estimates.num_second_best)
          : ((10 + heap_hdr->estimates.tail_second_best - heap_hdr->estimates.head_second_best)
         == heap_hdr->estimates.num_second_best));

      heap_hdr->estimates.num_substitutions = 1;
    }
}

/*
 * heap_stats_put_second_best () - Get a free page from second best hint array
 *   return: NO_ERROR or ER_FAILED
 *   heap_hdr(in): Statistics of heap file
 *   vpid(out): VPID to get
 */
static int
heap_stats_get_second_best (HEAP_HDR_STATS * heap_hdr, VPID * vpid)
{
  int head;

  assert (vpid != NULL);

  if (heap_hdr->estimates.num_second_best == 0)
    {
      assert (heap_hdr->estimates.tail_second_best == heap_hdr->estimates.head_second_best);
      VPID_SET_NULL (vpid);
      return ER_FAILED;
    }

  head = heap_hdr->estimates.head_second_best;

  heap_hdr->estimates.num_second_best--;
  heap_hdr->estimates.head_second_best = HEAP_STATS_NEXT_BEST_INDEX (head);

  /* If both head and tail refer to the same index, the number of second best hints is 0. */
  assert (heap_hdr->estimates.num_second_best != HEAP_NUM_BEST_SPACESTATS);
  assert ((heap_hdr->estimates.tail_second_best >= heap_hdr->estimates.head_second_best)
      ? ((heap_hdr->estimates.tail_second_best - heap_hdr->estimates.head_second_best)
         == heap_hdr->estimates.num_second_best)
      : ((10 + heap_hdr->estimates.tail_second_best - heap_hdr->estimates.head_second_best)
         == heap_hdr->estimates.num_second_best));

  *vpid = heap_hdr->estimates.second_best[head];
  return NO_ERROR;
}

#if defined(ENABLE_UNUSED_FUNCTION)
/*
 * heap_stats_quick_num_fit_in_bestspace () - Guess the number of unit_size entries that
 *                                  can fit in best space
 *   return: number of units
 *   bestspace(in): Array of best pages along with their freespace
 *                  (The freespace fields may be updated as a SIDE EFFECT)
 *   num_entries(in): Number of estimated entries in best space.
 *   unit_size(in): Units of this size
 *   unfill_space(in): Unfill space on the pages
 *
 * Note: Find the number of units of "unit_size" that can fit in
 * current betsspace.
 */
static int
heap_stats_quick_num_fit_in_bestspace (HEAP_BESTSPACE * bestspace, int num_entries, int unit_size, int unfill_space)
{
  int total_nunits = 0;
  int i;

  if (unit_size <= 0)
    {
      return ER_FAILED;
    }

  for (i = 0; i < num_entries; i++)
    {
      if ((bestspace[i].freespace - unfill_space) >= unit_size)
    {
      /* 
       * How many min_spaces can fit in this page
       */
      total_nunits += (bestspace[i].freespace - unfill_space) / unit_size;
    }
    }

  return total_nunits;
}
#endif

/*
 * heap_stats_find_page_in_bestspace () - Find a page within best space
 *                    statistics with the needed space
 *   return: HEAP_FINDPSACE (found, not found, or error)
 *   hfid(in): Object heap file identifier
 *   bestspace(in): Array of best pages along with their freespace
 *                  (The freespace fields may be updated as a SIDE EFFECT)
 *   idx_badspace(in/out): An index into best space with no so good space.
 *   needed_space(in): The needed space.
 *   scan_cache(in): Scan cache if any
 *   pgptr(out): Best page with enough space or NULL
 *
 * Note: Search for a page within the best space cache which has the
 * needed space. The free space fields of best space cache along
 * with some other index information are updated (as a side
 * effect) as the best space cache is accessed.
 */
static HEAP_FINDSPACE
heap_stats_find_page_in_bestspace (THREAD_ENTRY * thread_p, const HFID * hfid, HEAP_BESTSPACE * bestspace,
                   int *idx_badspace, int record_length, int needed_space, HEAP_SCANCACHE * scan_cache,
                   PGBUF_WATCHER * pg_watcher)
{
#define BEST_PAGE_SEARCH_MAX_COUNT 100

  HEAP_FINDSPACE found;
  int old_wait_msecs;
  int notfound_cnt;
  HEAP_STATS_ENTRY *ent;
  HEAP_BESTSPACE best;
  int rc;
  int idx_worstspace;
  int i, best_array_index = -1;
  bool hash_is_available;
  bool best_hint_is_used;

  assert (PGBUF_IS_CLEAN_WATCHER (pg_watcher));

  /* 
   * If a page is busy, don't wait continue looking for other pages in our
   * statistics. This will improve some contentions on the heap at the
   * expenses of storage.
   */

  /* LK_FORCE_ZERO_WAIT doesn't set error when deadlock occurs */
  old_wait_msecs = xlogtb_reset_wait_msecs (thread_p, LK_FORCE_ZERO_WAIT);

  found = HEAP_FINDSPACE_NOTFOUND;
  notfound_cnt = 0;
  best_array_index = 0;
  hash_is_available = prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES) > 0;

  while (found == HEAP_FINDSPACE_NOTFOUND)
    {
      best.freespace = -1;  /* init */
      best_hint_is_used = false;

      if (hash_is_available)
    {
      rc = pthread_mutex_lock (&heap_Bestspace->bestspace_mutex);

      while (notfound_cnt < BEST_PAGE_SEARCH_MAX_COUNT
         && (ent = (HEAP_STATS_ENTRY *) mht_get2 (heap_Bestspace->hfid_ht, hfid, NULL)) != NULL)
        {
          if (ent->best.freespace >= needed_space)
        {
          best = ent->best;
          assert (best.freespace > 0 && best.freespace <= PGLENGTH_MAX);
          break;
        }

          /* remove in memory bestspace */
          (void) mht_rem2 (heap_Bestspace->hfid_ht, &ent->hfid, ent, NULL, NULL);
          (void) mht_rem (heap_Bestspace->vpid_ht, &ent->best.vpid, NULL, NULL);
          (void) heap_stats_entry_free (thread_p, ent, NULL);
          ent = NULL;

          heap_Bestspace->num_stats_entries--;

          notfound_cnt++;
        }

      pthread_mutex_unlock (&heap_Bestspace->bestspace_mutex);
    }

      if (best.freespace == -1)
    {
      /* Maybe PRM_ID_HF_MAX_BESTSPACE_ENTRIES <= 0 or There is no best space in heap_Bestspace hashtable. We will
       * use bestspace hint in heap_header. */
      while (best_array_index < HEAP_NUM_BEST_SPACESTATS)
        {
          if (bestspace[best_array_index].freespace >= needed_space)
        {
          best.vpid = bestspace[best_array_index].vpid;
          best.freespace = bestspace[best_array_index].freespace;
          assert (best.freespace > 0 && best.freespace <= PGLENGTH_MAX);
          best_hint_is_used = true;
          break;
        }
          best_array_index++;
        }
    }

      if (best.freespace == -1)
    {
      break;        /* not found, exit loop */
    }

      /* If page could not be fixed, we will interrogate er_errid () to see the error type. If an error is already
       * set, the interrogation will be corrupted.
       * Make sure an error is not set.
       */
      if (er_errid () != NO_ERROR)
    {
      if (er_errid () == ER_INTERRUPTED)
        {
          /* interrupt arrives at any time */
          break;
        }
#if defined (SERVER_MODE)
      assert (er_errid () == ER_INTERRUPTED);
#endif /* SERVER_MODE */
      er_clear ();
    }

      pg_watcher->pgptr = heap_scan_pb_lock_and_fetch (thread_p, &best.vpid, OLD_PAGE, X_LOCK, scan_cache, pg_watcher);
      if (pg_watcher->pgptr == NULL)
    {
      /* 
       * Either we timeout and we want to continue in this case, or
       * we have another kind of problem.
       */
      switch (er_errid ())
        {
        case NO_ERROR:
          /* In case of latch-timeout in pgbuf_fix, the timeout error(ER_LK_PAGE_TIMEOUT) is not set, because lock
           * wait time is LK_FORCE_ZERO_WAIT. So we will just continue to find another page. */
          break;

        case ER_INTERRUPTED:
          found = HEAP_FINDSPACE_ERROR;
          break;

        default:
          /* 
           * Something went wrong, we are unable to fetch this page.
           */
          if (best_hint_is_used == true)

        {
          assert (best_array_index < HEAP_NUM_BEST_SPACESTATS);
          bestspace[best_array_index].freespace = 0;
        }
          else
        {
          (void) heap_stats_del_bestspace_by_vpid (thread_p, &best.vpid);
        }
          found = HEAP_FINDSPACE_ERROR;

          /* Do not allow unexpected errors. */
          assert (false);
          break;
        }
    }
      else
    {
      best.freespace = spage_max_space_for_new_record (thread_p, pg_watcher->pgptr);
      if (best.freespace >= needed_space)
        {
          /* 
           * Decrement by only the amount space needed by the caller. Don't
           * include the unfill factor
           */
          best.freespace -= record_length + heap_Slotted_overhead;
          found = HEAP_FINDSPACE_FOUND;
        }

      if (hash_is_available)
        {
          /* Add or refresh the free space of the page */
          (void) heap_stats_add_bestspace (thread_p, hfid, &best.vpid, best.freespace);
        }

      if (best_hint_is_used == true)
        {
          assert (VPID_EQ (&best.vpid, &(bestspace[best_array_index].vpid)));
          assert (best_array_index < HEAP_NUM_BEST_SPACESTATS);

          bestspace[best_array_index].freespace = best.freespace;
        }

      if (found != HEAP_FINDSPACE_FOUND)
        {
          pgbuf_ordered_unfix (thread_p, pg_watcher);
        }
    }

      if (found == HEAP_FINDSPACE_NOTFOUND)
    {
      if (best_hint_is_used)
        {
          /* Increment best_array_index for next search */
          best_array_index++;
        }
      else
        {
          notfound_cnt++;
        }
    }
    }

  idx_worstspace = 0;
  for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      /* find worst space in bestspace */
      if (bestspace[idx_worstspace].freespace > bestspace[i].freespace)
    {
      idx_worstspace = i;
    }

      /* update bestspace of heap header page if found best page at memory hash table */
      if (best_hint_is_used == false && found == HEAP_FINDSPACE_FOUND && VPID_EQ (&best.vpid, &bestspace[i].vpid))
    {
      bestspace[i].freespace = best.freespace;
    }
    }

  /* 
   * Set the idx_badspace to the index with the smallest free space
   * which may not be accurate. This is used for future lookups (where to
   * start) into the findbest space ring.
   */
  *idx_badspace = idx_worstspace;

  /* 
   * Reset back the timeout value of the transaction
   */
  (void) xlogtb_reset_wait_msecs (thread_p, old_wait_msecs);

  return found;
}

/*
 * heap_stats_find_best_page () - Find a page with the needed space.
 *   return: pointer to page with enough space or NULL
 *   hfid(in): Object heap file identifier
 *   needed_space(in): The minimal space needed
 *   isnew_rec(in): Are we inserting a new record to the heap ?
 *   newrec_size(in): Size of the new record
 *   scan_cache(in/out): Scan cache used to estimate the best space pages
 *
 * Note: Find a page among the set of best pages of the heap which has
 * the needed space. If we do not find any page, a new page is
 * allocated. The heap header and the scan cache may be updated
 * as a side effect to reflect more accurate space on some of the
 * set of best pages.
 */
static PAGE_PTR
heap_stats_find_best_page (THREAD_ENTRY * thread_p, const HFID * hfid, int needed_space, bool isnew_rec,
               int newrec_size, HEAP_SCANCACHE * scan_cache, PGBUF_WATCHER * pg_watcher)
{
  VPID vpid;            /* Volume and page identifiers */
  LOG_DATA_ADDR addr_hdr;   /* Address of logging data */
  RECDES hdr_recdes;        /* Record descriptor to point to space statistics */
  HEAP_HDR_STATS *heap_hdr; /* Heap header */
  VPID *hdr_vpidp;
  int total_space;
  int try_find, try_sync;
  int num_pages_found;
  float other_high_best_ratio;
  PGBUF_WATCHER hdr_page_watcher;
  int error_code = NO_ERROR;

  /* 
   * Try to use the space cache for as much information as possible to avoid
   * fetching and updating the header page a lot.
   */

  assert (scan_cache == NULL || scan_cache->cache_last_fix_page == false || scan_cache->page_watcher.pgptr == NULL);
  PGBUF_INIT_WATCHER (&hdr_page_watcher, PGBUF_ORDERED_HEAP_HDR, hfid);

  /* 
   * Get the heap header in exclusive mode since it is going to be changed.
   *
   * Note: to avoid any possibilities of deadlocks, I should not have any locks
   *       on the heap at this moment.
   *       That is, we must assume that locking the header of the heap in
   *       exclusive mode, the rest of the heap is locked.
   */

  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;

  addr_hdr.vfid = &hfid->vfid;
  addr_hdr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;

  error_code = pgbuf_ordered_fix (thread_p, &vpid, OLD_PAGE, PGBUF_LATCH_WRITE, &hdr_page_watcher);
  if (error_code != NO_ERROR)
    {
      /* something went wrong. Unable to fetch header page */
      ASSERT_ERROR ();
      return NULL;
    }
  assert (hdr_page_watcher.pgptr != NULL);

  (void) pgbuf_check_page_ptype (thread_p, hdr_page_watcher.pgptr, PAGE_HEAP);

  if (spage_get_record (thread_p, hdr_page_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &hdr_recdes, PEEK) != S_SUCCESS)
    {
      assert (false);
      pgbuf_ordered_unfix (thread_p, &hdr_page_watcher);
      return NULL;
    }

  heap_hdr = (HEAP_HDR_STATS *) hdr_recdes.data;

  if (isnew_rec == true)
    {
      heap_hdr->estimates.num_recs += 1;
      if (newrec_size > DB_PAGESIZE)
    {
      heap_hdr->estimates.num_pages += CEIL_PTVDIV (newrec_size, DB_PAGESIZE);
    }
    }
  heap_hdr->estimates.recs_sumlen += (float) newrec_size;

  assert (!heap_is_big_length (needed_space));
  /* Take into consideration the unfill factor for pages with objects */
  total_space = needed_space + heap_Slotted_overhead + heap_hdr->unfill_space;
  if (heap_is_big_length (total_space))
    {
      total_space = needed_space + heap_Slotted_overhead;
    }

  try_find = 0;
  while (true)
    {
      try_find++;
      assert (pg_watcher->pgptr == NULL);
      if (heap_stats_find_page_in_bestspace (thread_p, hfid, heap_hdr->estimates.best, &(heap_hdr->estimates.head),
                         needed_space, total_space, scan_cache, pg_watcher) == HEAP_FINDSPACE_ERROR)
    {
      ASSERT_ERROR ();
      assert (pg_watcher->pgptr == NULL);
      pgbuf_ordered_unfix (thread_p, &hdr_page_watcher);
      return NULL;
    }
      if (pg_watcher->pgptr != NULL)
    {
      /* found the page */
      break;
    }

      assert (hdr_page_watcher.page_was_unfixed == false);

      if (heap_hdr->estimates.num_other_high_best <= 0 || heap_hdr->estimates.num_pages <= 0)
    {
      assert (heap_hdr->estimates.num_pages > 0);
      other_high_best_ratio = 0;
    }
      else
    {
      other_high_best_ratio =
        (float) heap_hdr->estimates.num_other_high_best / (float) heap_hdr->estimates.num_pages;
    }

      if (try_find >= 2 || other_high_best_ratio < HEAP_BESTSPACE_SYNC_THRESHOLD)
    {
      /* We stop to find free pages if: (1) we have tried to do it twice (2) it is first trying but we have no
       * hints Regarding (2), we will find free pages by heap_stats_sync_bestspace only if we know that a free page 
       * exists somewhere. and (num_other_high_best/total page) > HEAP_BESTSPACE_SYNC_THRESHOLD.
       * num_other_high_best means the number of free pages existing somewhere in the heap file. */
      break;
    }

      /* 
       * The followings will try to find free pages and fill best hints with them.
       */

      if (scan_cache != NULL)
    {
      assert (HFID_EQ (hfid, &scan_cache->node.hfid));
      assert (scan_cache->file_type != FILE_UNKNOWN_TYPE);
    }

      hdr_vpidp = pgbuf_get_vpid_ptr (hdr_page_watcher.pgptr);

      try_sync = 0;
      do
    {
      try_sync++;
      er_log_debug (ARG_FILE_LINE,
            "heap_stats_find_best_page: call heap_stats_sync_bestspace() "
            "hfid { vfid  { fileid %d volid %d } hpgid %d } hdr_vpid { pageid %d volid %d } "
            "scan_all %d ", hfid->vfid.fileid, hfid->vfid.volid, hfid->hpgid, hdr_vpidp->pageid,
            hdr_vpidp->volid, 0);

      num_pages_found = heap_stats_sync_bestspace (thread_p, hfid, heap_hdr, hdr_vpidp, false, true);
      if (num_pages_found < 0)
        {
          pgbuf_ordered_unfix (thread_p, &hdr_page_watcher);
          ASSERT_ERROR ();
          return NULL;
        }
    }
      while (num_pages_found == 0 && try_sync <= 2);

      /* If we cannot find free pages, give up. */
      if (num_pages_found <= 0)
    {
      break;
    }
    }

  if (pg_watcher->pgptr == NULL)
    {
      /* 
       * None of the best pages has the needed space, allocate a new page.
       * Set the head to the index with the smallest free space, which may not
       * be accurate.
       */
      if (heap_vpid_alloc (thread_p, hfid, hdr_page_watcher.pgptr, heap_hdr, scan_cache, pg_watcher) != NO_ERROR)
    {
      ASSERT_ERROR ();
      pgbuf_ordered_unfix (thread_p, &hdr_page_watcher);
      return NULL;
    }
      assert (pg_watcher->pgptr != NULL || er_errid () == ER_INTERRUPTED
          || er_errid () == ER_FILE_NOT_ENOUGH_PAGES_IN_DATABASE);
    }

  addr_hdr.pgptr = hdr_page_watcher.pgptr;
  log_skip_logging (thread_p, &addr_hdr);
  pgbuf_ordered_set_dirty_and_free (thread_p, &hdr_page_watcher);

  return pg_watcher->pgptr;
}

/*
 * heap_stats_sync_bestspace () - Synchronize the statistics of best space
 *   return: the number of pages found
 *   hfid(in): Heap file identifier
 *   heap_hdr(in): Heap header (Heap header page should be acquired in
 *                 exclusive mode)
 *   hdr_vpid(in):
 *   scan_all(in): Scan the whole heap or stop after HEAP_NUM_BEST_SPACESTATS
 *                best pages have been found.
 *   can_cycle(in): True, it allows to go back to beginning of the heap.
 *                 FALSE, don't go back to beginning of the heap. FALSE is used
 *                 when it is known that there is not free space at the
 *                 beginning of heap. For example, it can be used when we
 *                 pre-allocate. pages
 *
 * Note: Synchronize for best space, so that we can reuse heap space as
 * much as possible.
 *
 * Note: This function does not do any logging.
 */
static int
heap_stats_sync_bestspace (THREAD_ENTRY * thread_p, const HFID * hfid, HEAP_HDR_STATS * heap_hdr, VPID * hdr_vpid,
               bool scan_all, bool can_cycle)
{
  int i, best, num_high_best, num_other_best, start_pos;
  VPID vpid = { NULL_PAGEID, NULL_VOLID };
  VPID start_vpid = { NULL_PAGEID, NULL_VOLID };
  VPID next_vpid = { NULL_PAGEID, NULL_VOLID };
  VPID stopat_vpid = { NULL_PAGEID, NULL_VOLID };
  int num_pages = 0;
  int num_recs = 0;
  float recs_sumlen = 0.0;
  int free_space = 0;
  int min_freespace;
  int ret = NO_ERROR;
  int npages = 0, nrecords = 0, rec_length;
  int num_iterations = 0, max_iterations;
  HEAP_BESTSPACE *best_pages_hint_p;
  bool iterate_all = false;
  bool search_all = false;
  PGBUF_WATCHER pg_watcher;
  PGBUF_WATCHER old_pg_watcher;
#if defined (CUBRID_DEBUG)
  TSC_TICKS start_tick, end_tick;
  TSCTIMEVAL tv_diff;

  float elapsed;

  tsc_getticks (&start_tick);
#endif /* CUBRID_DEBUG */

  perfmon_inc_stat (thread_p, PSTAT_HEAP_NUM_STATS_SYNC_BESTSPACE);
  PGBUF_INIT_WATCHER (&pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&old_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  min_freespace = heap_stats_get_min_freespace (heap_hdr);

  best = 0;
  start_pos = -1;
  num_high_best = num_other_best = 0;

  if (scan_all != true)
    {
      if (prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES) > 0)
    {
      search_all = true;
      start_pos = -1;
      next_vpid = heap_hdr->estimates.full_search_vpid;
    }
      else
    {
      if (heap_hdr->estimates.num_high_best > 0)
        {
          /* Use recently inserted one first. */
          start_pos = HEAP_STATS_PREV_BEST_INDEX (heap_hdr->estimates.head);
          for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
        {
          if (!VPID_ISNULL (&heap_hdr->estimates.best[start_pos].vpid))
            {
              next_vpid = heap_hdr->estimates.best[start_pos].vpid;
              start_vpid = next_vpid;
              break;
            }

          start_pos = HEAP_STATS_PREV_BEST_INDEX (start_pos);
        }
        }
      else
        {
          /* If there are hint pages in second best array, we will try to use it first. Otherwise, we will search
           * all pages in the file. */
          if (heap_hdr->estimates.num_second_best > 0)
        {
          if (heap_stats_get_second_best (heap_hdr, &next_vpid) != NO_ERROR)
            {
              /* This should not be happened. */
              assert (false);
              search_all = true;
            }
        }
          else
        {
          search_all = true;
        }

          if (search_all == true)
        {
          assert (VPID_ISNULL (&next_vpid));
          next_vpid = heap_hdr->estimates.full_search_vpid;
        }

          start_vpid = next_vpid;
          start_pos = -1;
        }
    }

      if (can_cycle == true)
    {
      stopat_vpid = next_vpid;
    }
    }

  if (VPID_ISNULL (&next_vpid))
    {
      /* 
       * Start from beginning of heap due to lack of statistics.
       */
      next_vpid.volid = hfid->vfid.volid;
      next_vpid.pageid = hfid->hpgid;
      start_vpid = next_vpid;
      start_pos = -1;
      can_cycle = false;
    }

  /* 
   * Note that we do not put any locks on the pages that we are scanning
   * since the best space array is only used for hints, and it is OK
   * if it is a little bit wrong.
   */
  best_pages_hint_p = heap_hdr->estimates.best;

  num_iterations = 0;
  max_iterations = MIN ((int) (heap_hdr->estimates.num_pages * 0.2), heap_Find_best_page_limit);
  max_iterations = MAX (max_iterations, HEAP_NUM_BEST_SPACESTATS);

  while (!VPID_ISNULL (&next_vpid) || can_cycle == true)
    {
      if (can_cycle == true && VPID_ISNULL (&next_vpid))
    {
      /* 
       * Go back to beginning of heap looking for good pages with a lot of
       * free space
       */
      next_vpid.volid = hfid->vfid.volid;
      next_vpid.pageid = hfid->hpgid;
      can_cycle = false;
    }

      while ((scan_all == true || num_high_best < HEAP_NUM_BEST_SPACESTATS) && !VPID_ISNULL (&next_vpid)
         && (can_cycle == true || !VPID_EQ (&next_vpid, &stopat_vpid)))
    {
      if (scan_all == false)
        {
          if (++num_iterations > max_iterations)
        {
          er_log_debug (ARG_FILE_LINE,
                "heap_stats_sync_bestspace: num_iterations %d best %d "
                "next_vpid { pageid %d volid %d }\n", num_iterations, num_high_best, next_vpid.pageid,
                next_vpid.volid);

          /* TODO: Do we really need to update the last scanned */
          /* in case we found less than 10 pages. */
          /* It is obivous we didn't find any pages. */
          if (start_pos != -1 && num_high_best == 0)
            {
              /* Delete a starting VPID. */
              VPID_SET_NULL (&best_pages_hint_p[start_pos].vpid);
              best_pages_hint_p[start_pos].freespace = 0;

              heap_hdr->estimates.num_high_best--;
            }
          iterate_all = true;
          break;
        }
        }

      vpid = next_vpid;
      ret = pgbuf_ordered_fix (thread_p, &vpid, OLD_PAGE_PREVENT_DEALLOC, PGBUF_LATCH_READ, &pg_watcher);
      if (ret != NO_ERROR)
        {
          break;
        }
      (void) pgbuf_check_page_ptype (thread_p, pg_watcher.pgptr, PAGE_HEAP);

      if (old_pg_watcher.pgptr != NULL)
        {
          pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
        }

      ret = heap_vpid_next (thread_p, hfid, pg_watcher.pgptr, &next_vpid);
      if (ret != NO_ERROR)
        {
          assert (false);
          pgbuf_ordered_unfix (thread_p, &pg_watcher);
          break;
        }
      if (search_all)
        {
          /* Save the last position to be searched next time. */
          heap_hdr->estimates.full_search_vpid = next_vpid;
        }

      spage_collect_statistics (pg_watcher.pgptr, &npages, &nrecords, &rec_length);

      num_pages += npages;
      num_recs += nrecords;
      recs_sumlen += rec_length;

      free_space = spage_max_space_for_new_record (thread_p, pg_watcher.pgptr);

      if (free_space >= min_freespace && free_space > HEAP_DROP_FREE_SPACE)
        {
          if (prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES) > 0)
        {
          (void) heap_stats_add_bestspace (thread_p, hfid, &vpid, free_space);
        }

          if (num_high_best < HEAP_NUM_BEST_SPACESTATS)
        {
          best_pages_hint_p[best].vpid = vpid;
          best_pages_hint_p[best].freespace = free_space;

          best = HEAP_STATS_NEXT_BEST_INDEX (best);
          num_high_best++;
        }
          else
        {
          num_other_best++;
        }
        }

      pgbuf_replace_watcher (thread_p, &pg_watcher, &old_pg_watcher);
    }

      assert (pg_watcher.pgptr == NULL);
      if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }

      if (scan_all == false
      && (iterate_all == true || num_high_best == HEAP_NUM_BEST_SPACESTATS
          || (can_cycle == false && VPID_EQ (&next_vpid, &stopat_vpid))))
    {
      break;
    }

      VPID_SET_NULL (&next_vpid);
    }

  er_log_debug (ARG_FILE_LINE,
        "heap_stats_sync_bestspace: scans from {%d|%d} to {%d|%d}, num_iterations(%d) "
        "max_iterations(%d) num_high_best(%d)\n", start_vpid.volid, start_vpid.pageid, vpid.volid, vpid.pageid,
        num_iterations, max_iterations, num_high_best);

  /* If we have scanned all pages, we should update all statistics even if we have not found any hints. This logic is
   * used to handle "select count(*) from table". */
  if (scan_all == false && num_high_best == 0 && heap_hdr->estimates.num_second_best == 0)
    {
      return 0;
    }

  if (num_high_best < HEAP_NUM_BEST_SPACESTATS)
    {
      for (i = best; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      VPID_SET_NULL (&best_pages_hint_p[i].vpid);
      best_pages_hint_p[i].freespace = 0;
    }
    }

  heap_hdr->estimates.head = best;  /* reinit */
  heap_hdr->estimates.num_high_best = num_high_best;
  assert (heap_hdr->estimates.head >= 0 && heap_hdr->estimates.head < HEAP_NUM_BEST_SPACESTATS
      && heap_hdr->estimates.num_high_best <= HEAP_NUM_BEST_SPACESTATS);

  if (scan_all == true || heap_hdr->estimates.num_pages <= num_pages)
    {
      /* 
       * We scan the whole heap.
       * Reset its statistics with new found statistics
       */
      heap_hdr->estimates.num_other_high_best = num_other_best;
      heap_hdr->estimates.num_pages = num_pages;
      heap_hdr->estimates.num_recs = num_recs;
      heap_hdr->estimates.recs_sumlen = recs_sumlen;
    }
  else
    {
      /* 
       * We did not scan the whole heap.
       * We reset only some of its statistics since we do not have any idea
       * which ones are better the ones that are currently recorded or the ones
       * just found.
       */
      heap_hdr->estimates.num_other_high_best -= heap_hdr->estimates.num_high_best;

      if (heap_hdr->estimates.num_other_high_best < num_other_best)
    {
      heap_hdr->estimates.num_other_high_best = num_other_best;
    }

      if (num_recs > heap_hdr->estimates.num_recs || recs_sumlen > heap_hdr->estimates.recs_sumlen)
    {
      heap_hdr->estimates.num_pages = num_pages;
      heap_hdr->estimates.num_recs = num_recs;
      heap_hdr->estimates.recs_sumlen = recs_sumlen;
    }
    }

#if defined (CUBRID_DEBUG)
  tsc_getticks (&end_tick);
  tsc_elapsed_time_usec (&tv_diff, end_tick, start_tick);
  elapsed = (float) tv_diff.tv_sec * 1000000;
  elapsed += (float) tv_diff.tv_usec;
  elapsed /= 1000000;

  er_log_debug (ARG_FILE_LINE, "heap_stats_sync_bestspace: elapsed time %.6f", elapsed);
#endif /* CUBRID_DEBUG */

  return num_high_best;
}

/*
 * heap_get_last_page () - Get the last page pointer.
 *   return: error code
 *   hfid(in): Object heap file identifier
 *   heap_hdr(in): The heap header structure
 *   scan_cache(in): Scan cache
 *   last_vpid(out): VPID of the last page
 *
 * Note: The last vpid is saved on heap header. We log it and should be the right VPID.
 */
static int
heap_get_last_page (THREAD_ENTRY * thread_p, const HFID * hfid, HEAP_HDR_STATS * heap_hdr, HEAP_SCANCACHE * scan_cache,
            VPID * last_vpid, PGBUF_WATCHER * pg_watcher)
{
  int error_code = NO_ERROR;

  assert (pg_watcher != NULL);
  assert (last_vpid != NULL);
  assert (!VPID_ISNULL (&heap_hdr->estimates.last_vpid));

  *last_vpid = heap_hdr->estimates.last_vpid;
  pg_watcher->pgptr = heap_scan_pb_lock_and_fetch (thread_p, last_vpid, OLD_PAGE, X_LOCK, scan_cache, pg_watcher);
  if (pg_watcher->pgptr == NULL)
    {
      ASSERT_ERROR_AND_SET (error_code);
      return error_code;
    }

#if !defined (NDEBUG)
  {
    RECDES recdes;
    HEAP_CHAIN *chain;
    if (spage_get_record (thread_p, pg_watcher->pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
      {
    assert (false);
    pgbuf_ordered_unfix (thread_p, pg_watcher);
    return ER_FAILED;
      }
    chain = (HEAP_CHAIN *) recdes.data;
    assert (VPID_ISNULL (&chain->next_vpid));
  }
#endif /* !NDEBUG */

  return NO_ERROR;
}

/*
 * heap_get_last_vpid () - Get last heap page VPID from heap file header
 *
 * return      : Error code
 * thread_p (in)   : Thread entry
 * hfid (in)       : Heap file identifier
 * last_vpid (out) : Last heap page VPID
 */
STATIC_INLINE int
heap_get_last_vpid (THREAD_ENTRY * thread_p, const HFID * hfid, VPID * last_vpid)
{
  PGBUF_WATCHER watcher_heap_header;
  VPID vpid_heap_header;
  HEAP_HDR_STATS *hdr_stats = NULL;

  int error_code = NO_ERROR;

  PGBUF_INIT_WATCHER (&watcher_heap_header, PGBUF_ORDERED_HEAP_HDR, hfid);

  VPID_SET_NULL (last_vpid);

  vpid_heap_header.volid = hfid->vfid.volid;
  vpid_heap_header.pageid = hfid->hpgid;
  error_code = pgbuf_ordered_fix (thread_p, &vpid_heap_header, OLD_PAGE, PGBUF_LATCH_READ, &watcher_heap_header);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }

  hdr_stats = heap_get_header_stats_ptr (thread_p, watcher_heap_header.pgptr);
  if (hdr_stats == NULL)
    {
      assert_release (false);
      pgbuf_ordered_unfix (thread_p, &watcher_heap_header);
      return ER_FAILED;
    }
  *last_vpid = hdr_stats->estimates.last_vpid;
  pgbuf_ordered_unfix (thread_p, &watcher_heap_header);
  return NO_ERROR;
}

/*
 * heap_get_header_stats_ptr () - Get pointer to heap header statistics.
 *
 * return       : Pointer to heap header statistics
 * page_header (in) : Heap header page
 */
STATIC_INLINE HEAP_HDR_STATS *
heap_get_header_stats_ptr (THREAD_ENTRY * thread_p, PAGE_PTR page_header)
{
  RECDES recdes;

  if (spage_get_record (thread_p, page_header, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      assert_release (false);
      return NULL;
    }
  return (HEAP_HDR_STATS *) recdes.data;
}

/*
 * heap_copy_header_stats () - Copy heap header statistics
 *
 * return         : Error code
 * page_header (in)   : Heap header page
 * header_stats (out) : Heap header statistics
 */
STATIC_INLINE int
heap_copy_header_stats (THREAD_ENTRY * thread_p, PAGE_PTR page_header, HEAP_HDR_STATS * header_stats)
{
  RECDES recdes;

  recdes.data = (char *) header_stats;
  recdes.area_size = sizeof (*header_stats);
  if (spage_get_record (thread_p, page_header, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, COPY) != S_SUCCESS)
    {
      assert_release (false);
      return ER_FAILED;
    }
  return NO_ERROR;
}

/*
 * heap_get_chain_ptr () - Get pointer to chain in heap page
 *
 * return     : Pointer to chain in heap page
 * page_heap (in) : Heap page
 */
STATIC_INLINE HEAP_CHAIN *
heap_get_chain_ptr (THREAD_ENTRY * thread_p, PAGE_PTR page_heap)
{
  RECDES recdes;

  if (spage_get_record (thread_p, page_heap, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      assert_release (false);
      return NULL;
    }
  return (HEAP_CHAIN *) recdes.data;
}

/*
 * heap_copy_chain () - Copy chain from heap page
 *
 * return     : Error code
 * page_heap (in) : Heap page
 * chain (out)    : Heap chain
 */
STATIC_INLINE int
heap_copy_chain (THREAD_ENTRY * thread_p, PAGE_PTR page_heap, HEAP_CHAIN * chain)
{
  RECDES recdes;

  if (spage_get_record (thread_p, page_heap, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      assert_release (false);
      return ER_FAILED;
    }
  assert (recdes.length >= (int) sizeof (*chain));
  memcpy (chain, recdes.data, sizeof (*chain));
  return NO_ERROR;
}

/*
 * heap_vpid_init_new () - FILE_INIT_PAGE_FUNC for heap non-header pages
 *
 * return    : Error code
 * thread_p (in) : Thread entry
 * page (in)     : New heap file page
 * args (in)     : HEAP_CHAIN *
 */
static int
heap_vpid_init_new (THREAD_ENTRY * thread_p, PAGE_PTR page, void *args)
{
  LOG_DATA_ADDR addr = LOG_DATA_ADDR_INITIALIZER;
  HEAP_CHAIN chain;
  RECDES recdes;
  INT16 slotid;
  int sp_success;

  assert (page != NULL);
  assert (args != NULL);

  chain = *(HEAP_CHAIN *) args; /* get chain from args. it is already initialized */

  /* initialize new page. */
  addr.pgptr = page;
  pgbuf_set_page_ptype (thread_p, addr.pgptr, PAGE_HEAP);

  /* initialize the page and chain it with the previous last allocated page */
  spage_initialize (thread_p, addr.pgptr, heap_get_spage_type (), HEAP_MAX_ALIGN, SAFEGUARD_RVSPACE);

  recdes.area_size = recdes.length = sizeof (chain);
  recdes.type = REC_HOME;
  recdes.data = (char *) &chain;

  sp_success = spage_insert (thread_p, addr.pgptr, &recdes, &slotid);
  if (sp_success != SP_SUCCESS || slotid != HEAP_HEADER_AND_CHAIN_SLOTID)
    {
      assert (false);

      /* initialization has failed !! */
      if (sp_success != SP_SUCCESS)
    {
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
    }
      return ER_FAILED;
    }

  log_append_undoredo_data (thread_p, RVHF_NEWPAGE, &addr, 0, recdes.length, NULL, recdes.data);
  pgbuf_set_dirty (thread_p, addr.pgptr, DONT_FREE);
  return NO_ERROR;
}

/*
 * heap_vpid_alloc () - allocate, fetch, and initialize a new page
 *   return: error code
 *   hfid(in): Object heap file identifier
 *   hdr_pgptr(in): The heap page header
 *   heap_hdr(in): The heap header structure
 *   scan_cache(in): Scan cache
 *   new_pg_watcher(out): watcher for new page.
 *
 * Note: Allocate and initialize a new heap page. The heap header is
 * updated to reflect a newly allocated best space page and
 * the set of best space pages information may be updated to
 * include the previous best1 space page.
 */
static int
heap_vpid_alloc (THREAD_ENTRY * thread_p, const HFID * hfid, PAGE_PTR hdr_pgptr, HEAP_HDR_STATS * heap_hdr,
         HEAP_SCANCACHE * scan_cache, PGBUF_WATCHER * new_pg_watcher)
{
  VPID vpid;            /* Volume and page identifiers */
  LOG_DATA_ADDR addr = LOG_DATA_ADDR_INITIALIZER;   /* Address of logging data */
  int best;
  VPID last_vpid;
  PGBUF_WATCHER last_pg_watcher;
  HEAP_CHAIN new_page_chain;
  HEAP_HDR_STATS heap_hdr_prev = *heap_hdr;

  int error_code = NO_ERROR;

  assert (PGBUF_IS_CLEAN_WATCHER (new_pg_watcher));

  PGBUF_INIT_WATCHER (&last_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  addr.vfid = &hfid->vfid;
  addr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;

  error_code = heap_get_last_page (thread_p, hfid, heap_hdr, scan_cache, &last_vpid, &last_pg_watcher);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }
  if (last_pg_watcher.pgptr == NULL)
    {
      /* something went wrong, return error */
      assert_release (false);
      return ER_FAILED;
    }
  assert (!VPID_ISNULL (&last_vpid));

  log_sysop_start (thread_p);

  /* init chain for new page */
  new_page_chain.class_oid = heap_hdr->class_oid;
  new_page_chain.prev_vpid = last_vpid;
  VPID_SET_NULL (&new_page_chain.next_vpid);
  new_page_chain.max_mvccid = MVCCID_NULL;
  new_page_chain.flags = 0;
  HEAP_PAGE_SET_VACUUM_STATUS (&new_page_chain, HEAP_PAGE_VACUUM_NONE);

  /* allocate new page and initialize it */
  error_code = file_alloc (thread_p, &hfid->vfid, heap_vpid_init_new, &new_page_chain, &vpid, NULL);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto error;
    }

  /* add link from previous last page */
  addr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;

  if (last_pg_watcher.pgptr == hdr_pgptr)
    {
      heap_hdr->next_vpid = vpid;
      /* will be logged later */
    }
  else
    {
      HEAP_CHAIN *chain, chain_prev;

      /* get chain */
      chain = heap_get_chain_ptr (thread_p, last_pg_watcher.pgptr);
      if (chain == NULL)
    {
      assert_release (false);
      error_code = ER_FAILED;
      goto error;
    }
      /* update chain */
      /* save old chain for logging */
      chain_prev = *chain;
      /* change next link */
      chain->next_vpid = vpid;

      /* log change */
      addr.pgptr = last_pg_watcher.pgptr;
      log_append_undoredo_data (thread_p, RVHF_CHAIN, &addr, sizeof (HEAP_CHAIN), sizeof (HEAP_CHAIN), &chain_prev,
                chain);
      pgbuf_set_dirty (thread_p, addr.pgptr, DONT_FREE);
    }

  pgbuf_ordered_unfix (thread_p, &last_pg_watcher);

  /* now update header statistics for best1 space page. the changes to the statistics are not logged. */
  /* last page hint */
  heap_hdr->estimates.last_vpid = vpid;
  heap_hdr->estimates.num_pages++;

  best = heap_hdr->estimates.head;
  heap_hdr->estimates.head = HEAP_STATS_NEXT_BEST_INDEX (best);
  if (VPID_ISNULL (&heap_hdr->estimates.best[best].vpid))
    {
      heap_hdr->estimates.num_high_best++;
      assert (heap_hdr->estimates.num_high_best <= HEAP_NUM_BEST_SPACESTATS);
    }
  else
    {
      if (heap_hdr->estimates.best[best].freespace > HEAP_DROP_FREE_SPACE)
    {
      heap_hdr->estimates.num_other_high_best++;
      heap_stats_put_second_best (heap_hdr, &heap_hdr->estimates.best[best].vpid);
    }
    }

  heap_hdr->estimates.best[best].vpid = vpid;
  heap_hdr->estimates.best[best].freespace = DB_PAGESIZE;

  if (prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES) > 0)
    {
      (void) heap_stats_add_bestspace (thread_p, hfid, &vpid, heap_hdr->estimates.best[best].freespace);
    }

  /* we really have nothing to lose from logging stats here and also it is good to have a certain last VPID. */
  addr.pgptr = hdr_pgptr;
  log_append_undoredo_data (thread_p, RVHF_STATS, &addr, sizeof (HEAP_HDR_STATS), sizeof (HEAP_HDR_STATS),
                &heap_hdr_prev, heap_hdr);
  log_sysop_commit (thread_p);

  /* fix new page */
  new_pg_watcher->pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, X_LOCK, scan_cache, new_pg_watcher);
  if (new_pg_watcher->pgptr == NULL)
    {
      ASSERT_ERROR_AND_SET (error_code);
      return error_code;
    }

  return NO_ERROR;

error:
  assert (error_code != NO_ERROR);

  if (last_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &last_pg_watcher);
    }
  log_sysop_abort (thread_p);

  return error_code;
}

/*
 * heap_vpid_remove () - Deallocate a heap page
 *   return: rm_vpid on success or NULL on error
 *   hfid(in): Object heap file identifier
 *   heap_hdr(in): The heap header stats
 *   rm_vpid(in): Page to remove
 *
 * Note: The given page is removed from the heap. The linked list of heap
 * pages is updated to remove this page, and the heap header may
 * be updated if this page was part of the statistics.
 */
static VPID *
heap_vpid_remove (THREAD_ENTRY * thread_p, const HFID * hfid, HEAP_HDR_STATS * heap_hdr, VPID * rm_vpid)
{
  RECDES rm_recdes;     /* Record descriptor which holds the chain of the page to be removed */
  HEAP_CHAIN *rm_chain;     /* Chain information of the page to be removed */
  VPID vpid;            /* Real identifier of previous page */
  LOG_DATA_ADDR addr;       /* Log address of previous page */
  RECDES recdes;        /* Record descriptor to page header */
  HEAP_CHAIN chain;     /* Chain to next and prev page */
  int sp_success;
  int i;
  PGBUF_WATCHER rm_pg_watcher;
  PGBUF_WATCHER prev_pg_watcher;

  PGBUF_INIT_WATCHER (&rm_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&prev_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  /* 
   * Make sure that this is not the header page since the header page cannot
   * be removed. If the header page is removed.. the heap is gone
   */

  if (rm_vpid->pageid == hfid->hpgid && rm_vpid->volid == hfid->vfid.volid)
    {
      er_log_debug (ARG_FILE_LINE, "heap_vpid_remove: Trying to remove header page = %d|%d of heap file = %d|%d|%d",
            (int) rm_vpid->volid, rm_vpid->pageid, (int) hfid->vfid.volid, hfid->vfid.fileid, hfid->hpgid);
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      goto error;
    }

  /* Get the chain record */
  rm_pg_watcher.pgptr = heap_scan_pb_lock_and_fetch (thread_p, rm_vpid, OLD_PAGE, X_LOCK, NULL, &rm_pg_watcher);
  if (rm_pg_watcher.pgptr == NULL)
    {
      /* Look like a system error. Unable to obtain chain header record */
      goto error;
    }

  if (spage_get_record (thread_p, rm_pg_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &rm_recdes, PEEK) != S_SUCCESS)
    {
      /* Look like a system error. Unable to obtain chain header record */
      goto error;
    }

  rm_chain = (HEAP_CHAIN *) rm_recdes.data;

  /* 
   * UPDATE PREVIOUS PAGE
   *
   * Update chain next field of previous last page
   * If previous page is the heap header page, it contains a heap header
   * instead of a chain.
   */

  vpid = rm_chain->prev_vpid;
  addr.vfid = &hfid->vfid;
  addr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;

  prev_pg_watcher.pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, X_LOCK, NULL, &prev_pg_watcher);
  if (prev_pg_watcher.pgptr == NULL)
    {
      /* something went wrong, return */
      goto error;
    }

  if (rm_pg_watcher.page_was_unfixed)
    {
      /* TODO : unexpected: need to reconsider the algorithm, if this is an ordinary case */
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PB_UNEXPECTED_PAGE_REFIX, 4, rm_vpid->volid, rm_vpid->pageid,
          vpid.volid, vpid.pageid);
      goto error;
    }

  /* 
   * Make sure that the page to be removed is not referenced on the heap
   * statistics
   */

  assert (heap_hdr != NULL);

  /* 
   * We cannot break in the following loop since a best page could be
   * duplicated
   */
  for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      if (VPID_EQ (&heap_hdr->estimates.best[i].vpid, rm_vpid))
    {
      VPID_SET_NULL (&heap_hdr->estimates.best[i].vpid);
      heap_hdr->estimates.best[i].freespace = 0;
      heap_hdr->estimates.head = i;
    }
    }

  if (VPID_EQ (&heap_hdr->estimates.last_vpid, rm_vpid))
    {
      /* If the page is the last page of the heap file, update the hint */
      heap_hdr->estimates.last_vpid = rm_chain->prev_vpid;
    }

  /* 
   * Is previous page the header page ?
   */
  if (vpid.pageid == hfid->hpgid && vpid.volid == hfid->vfid.volid)
    {
      /* 
       * PREVIOUS PAGE IS THE HEADER PAGE.
       * It contains a heap header instead of a chain record
       */
      heap_hdr->next_vpid = rm_chain->next_vpid;
    }
  else
    {
      /* 
       * PREVIOUS PAGE IS NOT THE HEADER PAGE.
       * It contains a chain...
       * We need to make sure that there is not references to the page to delete
       * in the statistics of the heap header
       */

      /* NOW check the PREVIOUS page */

      if (spage_get_record (thread_p, prev_pg_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      /* Look like a system error. Unable to obtain header record */
      goto error;
    }

      /* Copy the chain record to memory.. so we can log the changes */
      memcpy (&chain, recdes.data, sizeof (chain));

      /* Modify the chain of the previous page in memory */
      chain.next_vpid = rm_chain->next_vpid;

      /* Get the chain record */
      recdes.area_size = recdes.length = sizeof (chain);
      recdes.type = REC_HOME;
      recdes.data = (char *) &chain;

      /* Log the desired changes.. and then change the header */
      addr.pgptr = prev_pg_watcher.pgptr;
      log_append_undoredo_data (thread_p, RVHF_CHAIN, &addr, sizeof (chain), sizeof (chain), recdes.data, &chain);

      /* Now change the record */

      sp_success = spage_update (thread_p, prev_pg_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes);
      if (sp_success != SP_SUCCESS)
    {
      /* 
       * This look like a system error, size did not change, so why did it
       * fail
       */
      if (sp_success != SP_ERROR)
        {
          er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
        }
      goto error;
    }

    }

  /* Now set dirty, free and unlock the previous page */
  pgbuf_ordered_set_dirty_and_free (thread_p, &prev_pg_watcher);

  /* 
   * UPDATE NEXT PAGE
   *
   * Update chain previous field of next page
   */

  if (!(VPID_ISNULL (&rm_chain->next_vpid)))
    {
      vpid = rm_chain->next_vpid;
      addr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;

      prev_pg_watcher.pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, X_LOCK, NULL, &prev_pg_watcher);
      if (prev_pg_watcher.pgptr == NULL)
    {
      /* something went wrong, return */
      goto error;
    }

      /* Get the chain record */
      if (spage_get_record (thread_p, prev_pg_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      /* Look like a system error. Unable to obtain header record */
      goto error;
    }

      /* Copy the chain record to memory.. so we can log the changes */
      memcpy (&chain, recdes.data, sizeof (chain));

      /* Modify the chain of the next page in memory */
      chain.prev_vpid = rm_chain->prev_vpid;

      /* Log the desired changes.. and then change the header */
      addr.pgptr = prev_pg_watcher.pgptr;
      log_append_undoredo_data (thread_p, RVHF_CHAIN, &addr, sizeof (chain), sizeof (chain), recdes.data, &chain);

      /* Now change the record */
      recdes.area_size = recdes.length = sizeof (chain);
      recdes.type = REC_HOME;
      recdes.data = (char *) &chain;

      sp_success = spage_update (thread_p, prev_pg_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes);
      if (sp_success != SP_SUCCESS)
    {
      /* 
       * This look like a system error, size did not change, so why did it
       * fail
       */
      if (sp_success != SP_ERROR)
        {
          er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
        }
      goto error;
    }

      /* Now set dirty, free and unlock the next page */

      pgbuf_ordered_set_dirty_and_free (thread_p, &prev_pg_watcher);
    }

  /* Free the page to be deallocated and deallocate the page */
  pgbuf_ordered_unfix (thread_p, &rm_pg_watcher);

  if (file_dealloc (thread_p, &hfid->vfid, rm_vpid, FILE_HEAP) != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto error;
    }

  (void) heap_stats_del_bestspace_by_vpid (thread_p, rm_vpid);

  return rm_vpid;

error:
  if (rm_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &rm_pg_watcher);
    }
  if (addr.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &prev_pg_watcher);
    }

  return NULL;
}

/*
 * heap_remove_page_on_vacuum () - Remove heap page from heap file during
 *                 vacuum process. Function is trying to
 *                 be as least intrusive as possible and all
 *                 required pages are latched conditionally.
 *                 Give up on any failed operation.
 *
 * return    : True if page was deallocated, false if not.
 * thread_p (in) : Thread entry.
 * page_ptr (in) : Pointer to page being deallocated.
 * hfid (in)     : Heap file identifier.
 */
bool
heap_remove_page_on_vacuum (THREAD_ENTRY * thread_p, PAGE_PTR * page_ptr, HFID * hfid)
{
  VPID page_vpid = VPID_INITIALIZER;    /* VPID of page being removed. */
  VPID prev_vpid = VPID_INITIALIZER;    /* VPID of previous page. */
  VPID next_vpid = VPID_INITIALIZER;    /* VPID of next page. */
  VPID header_vpid = VPID_INITIALIZER;  /* VPID of heap header page. */
  HEAP_HDR_STATS heap_hdr;  /* Header header & stats. */
  HEAP_CHAIN chain;     /* Heap page header used to read and update page links. */
  RECDES copy_recdes;       /* Record to copy header from pages. */
  /* Buffer used for copy record. */
  char copy_recdes_buffer[MAX (sizeof (HEAP_CHAIN), sizeof (HEAP_HDR_STATS)) + MAX_ALIGNMENT];
  RECDES update_recdes;     /* Record containing updated header data. */
  int i = 0;            /* Iterator. */
  bool is_system_op_started = false;    /* Set to true once system operation is started. */
  PGBUF_WATCHER crt_watcher;    /* Watcher for current page. */
  PGBUF_WATCHER header_watcher; /* Watcher for header page. */
  PGBUF_WATCHER prev_watcher;   /* Watcher for previous page. */
  PGBUF_WATCHER next_watcher;   /* Watcher for next page. */

  /* Assert expected arguments. */
  /* Page to remove must be fixed. */
  assert (page_ptr != NULL && *page_ptr != NULL);
  /* Page to remove must be empty. */
  assert (spage_number_of_records (*page_ptr) <= 1);
  /* Heap file identifier must be known. */
  assert (hfid != NULL && !HFID_IS_NULL (hfid));

  /* Get VPID of page to be removed. */
  pgbuf_get_vpid (*page_ptr, &page_vpid);

  if (page_vpid.pageid == hfid->hpgid && page_vpid.volid == hfid->vfid.volid)
    {
      /* Cannot remove heap file header page. */
      return false;
    }

  /* Use page watchers to do the ordered fix. */
  PGBUF_INIT_WATCHER (&crt_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&header_watcher, PGBUF_ORDERED_HEAP_HDR, hfid);
  PGBUF_INIT_WATCHER (&prev_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&next_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  /* Current page is already fixed. Just attach watcher. */
  pgbuf_attach_watcher (thread_p, *page_ptr, PGBUF_LATCH_WRITE, hfid, &crt_watcher);

  /* Header vpid. */
  header_vpid.volid = hfid->vfid.volid;
  header_vpid.pageid = hfid->hpgid;

  /* Fix required pages: Heap header page. Previous page (always exists). Next page (if exists). */

  /* Fix header page first, because it has higher priority. */
  if (pgbuf_ordered_fix (thread_p, &header_vpid, OLD_PAGE, PGBUF_LATCH_WRITE, &header_watcher) != NO_ERROR)
    {
      /* Give up. */
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid, page_vpid.pageid);
      goto error;
    }
  assert (header_watcher.pgptr != NULL);

  if (crt_watcher.page_was_unfixed)
    {
      *page_ptr = crt_watcher.pgptr;    /* home was refixed */
    }

  /* Get previous and next page VPID's. */
  if (heap_vpid_prev (thread_p, hfid, *page_ptr, &prev_vpid) != NO_ERROR
      || heap_vpid_next (thread_p, hfid, *page_ptr, &next_vpid) != NO_ERROR)
    {
      /* Give up. */
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid, page_vpid.pageid);
      goto error;
    }

  /* Fix previous page if it is not same as header. */
  if (!VPID_ISNULL (&prev_vpid) && !VPID_EQ (&prev_vpid, &header_vpid))
    {
      if (pgbuf_ordered_fix (thread_p, &prev_vpid, OLD_PAGE, PGBUF_LATCH_WRITE, &prev_watcher) != NO_ERROR)
    {
      /* Give up. */
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid,
                 page_vpid.pageid);
      goto error;
    }
    }

  /* Fix next page if current page is not last in heap file. */
  if (!VPID_ISNULL (&next_vpid))
    {
      if (pgbuf_ordered_fix (thread_p, &next_vpid, OLD_PAGE, PGBUF_LATCH_WRITE, &next_watcher) != NO_ERROR)
    {
      /* Give up. */
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid,
                 page_vpid.pageid);
      goto error;
    }
    }

  /* All pages are fixed. */

  if (crt_watcher.page_was_unfixed)
    {
      *page_ptr = crt_watcher.pgptr;    /* home was refixed */

      if (spage_number_of_records (crt_watcher.pgptr) > 1)
    {
      /* Current page has new data. It is no longer a candidate for removal. */
      vacuum_er_log (VACUUM_ER_LOG_HEAP,
             "Candidate heap page %d|%d to remove was changed and has new data.", page_vpid.volid,
             page_vpid.pageid);
      goto error;
    }
    }

  /* recheck the dealloc flag after all latches are acquired */
  if (pgbuf_has_prevent_dealloc (crt_watcher.pgptr))
    {
      /* Even though we have fixed all required pages, somebody was doing a heap scan, and already reached our page. We 
       * cannot deallocate it. */
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Candidate heap page %d|%d to remove has waiters.", page_vpid.volid, page_vpid.pageid);
      goto error;
    }

  /* if we are here, the page should not be accessed by any active or vacuum workers. Active workers are prevented
   * from accessing it through heap scan, and direct references should not exist.
   * the function would not be called if any other vacuum workers would try to access the page. */
  if (pgbuf_has_any_waiters (crt_watcher.pgptr))
    {
      assert (false);
      vacuum_er_log_error (VACUUM_ER_LOG_HEAP, "%s", "Unexpected page waiters");
      goto error;
    }
  /* all good, we can deallocate the page */

  /* Start changes under the protection of system operation. */
  log_sysop_start (thread_p);
  is_system_op_started = true;

  /* Remove page from statistics in header page. */
  copy_recdes.data = PTR_ALIGN (copy_recdes_buffer, MAX_ALIGNMENT);
  copy_recdes.area_size = sizeof (heap_hdr);
  if (spage_get_record (thread_p, header_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &copy_recdes, COPY) != S_SUCCESS)
    {
      assert_release (false);
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid, page_vpid.pageid);
      goto error;
    }
  memcpy (&heap_hdr, copy_recdes.data, sizeof (heap_hdr));

  for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      if (VPID_EQ (&heap_hdr.estimates.best[i].vpid, &page_vpid))
    {
      VPID_SET_NULL (&heap_hdr.estimates.best[i].vpid);
      heap_hdr.estimates.best[i].freespace = 0;
      heap_hdr.estimates.head = i;
      heap_hdr.estimates.num_high_best--;
    }
      if (VPID_EQ (&heap_hdr.estimates.second_best[i], &page_vpid))
    {
      VPID_SET_NULL (&heap_hdr.estimates.second_best[i]);
    }
    }
  if (VPID_EQ (&heap_hdr.estimates.last_vpid, &page_vpid))
    {
      VPID_COPY (&heap_hdr.estimates.last_vpid, &prev_vpid);
    }
  if (VPID_EQ (&prev_vpid, &header_vpid))
    {
      /* Update next link. */
      VPID_COPY (&heap_hdr.next_vpid, &next_vpid);
    }
  if (VPID_EQ (&heap_hdr.estimates.full_search_vpid, &page_vpid))
    {
      VPID_SET_NULL (&heap_hdr.estimates.full_search_vpid);
    }

  /* Update header and log changes. */
  update_recdes.data = (char *) &heap_hdr;
  update_recdes.length = sizeof (heap_hdr);
  if (spage_update (thread_p, header_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &update_recdes) != SP_SUCCESS)
    {
      assert_release (false);
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid, page_vpid.pageid);
      goto error;
    }
  log_append_undoredo_data2 (thread_p, RVHF_STATS, &hfid->vfid, header_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID,
                 sizeof (heap_hdr), sizeof (heap_hdr), copy_recdes.data, update_recdes.data);
  pgbuf_set_dirty (thread_p, header_watcher.pgptr, DONT_FREE);

  /* Update links in previous and next page. */

  if (prev_watcher.pgptr != NULL)
    {
      /* Next link in previous page. */
      assert (!VPID_EQ (&header_vpid, &prev_vpid));
      copy_recdes.area_size = sizeof (chain);
      if (spage_get_record (thread_p, prev_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &copy_recdes, COPY) !=
      S_SUCCESS)
    {
      assert_release (false);
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid,
                 page_vpid.pageid);
      goto error;
    }
      memcpy (&chain, copy_recdes.data, copy_recdes.length);
      VPID_COPY (&chain.next_vpid, &next_vpid);
      update_recdes.data = (char *) &chain;
      update_recdes.length = sizeof (chain);
      if (spage_update (thread_p, prev_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &update_recdes) != SP_SUCCESS)
    {
      assert_release (false);
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid,
                 page_vpid.pageid);
      goto error;
    }
      log_append_undoredo_data2 (thread_p, RVHF_CHAIN, &hfid->vfid, prev_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID,
                 sizeof (chain), sizeof (chain), copy_recdes.data, update_recdes.data);
      pgbuf_set_dirty (thread_p, prev_watcher.pgptr, DONT_FREE);
    }

  if (next_watcher.pgptr != NULL)
    {
      /* Previous link in next page. */
      copy_recdes.area_size = sizeof (chain);
      if (spage_get_record (thread_p, next_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &copy_recdes, COPY) !=
      S_SUCCESS)
    {
      assert_release (false);
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid,
                 page_vpid.pageid);
      goto error;
    }
      memcpy (&chain, copy_recdes.data, sizeof (chain));
      VPID_COPY (&chain.prev_vpid, &prev_vpid);
      update_recdes.data = (char *) &chain;
      update_recdes.length = sizeof (chain);

      if (spage_update (thread_p, next_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &update_recdes) != SP_SUCCESS)
    {
      assert_release (false);
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid,
                 page_vpid.pageid);
      goto error;
    }
      log_append_undoredo_data2 (thread_p, RVHF_CHAIN, &hfid->vfid, next_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID,
                 sizeof (chain), sizeof (chain), copy_recdes.data, update_recdes.data);
      pgbuf_set_dirty (thread_p, next_watcher.pgptr, DONT_FREE);
    }

  /* Unfix current page. */
  pgbuf_ordered_unfix_and_init (thread_p, *page_ptr, &crt_watcher);
  /* Deallocate current page. */
  if (file_dealloc (thread_p, &hfid->vfid, &page_vpid, FILE_HEAP) != NO_ERROR)
    {
      ASSERT_ERROR ();
      vacuum_er_log_warning (VACUUM_ER_LOG_HEAP,
                 "Could not remove candidate empty heap page %d|%d.", page_vpid.volid, page_vpid.pageid);
      goto error;
    }

  /* Remove page from best space cached statistics. */
  (void) heap_stats_del_bestspace_by_vpid (thread_p, &page_vpid);

  /* Finished. */
  log_sysop_commit (thread_p);
  is_system_op_started = false;

  /* Unfix all pages. */
  if (next_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &next_watcher);
    }
  if (prev_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &prev_watcher);
    }
  pgbuf_ordered_unfix (thread_p, &header_watcher);

  /* Page removed successfully. */
  vacuum_er_log (VACUUM_ER_LOG_HEAP, "Successfully remove heap page %d|%d.", page_vpid.volid, page_vpid.pageid);
  return true;

error:
  if (is_system_op_started)
    {
      log_sysop_abort (thread_p);
    }
  if (next_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &next_watcher);
    }
  if (prev_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &prev_watcher);
    }
  if (header_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &header_watcher);
    }
  if (*page_ptr != NULL)
    {
      if (*page_ptr != crt_watcher.pgptr)
    {
      /* jumped to here while fixing pages */
      assert (crt_watcher.page_was_unfixed);
      *page_ptr = crt_watcher.pgptr;
    }
      assert (crt_watcher.pgptr == *page_ptr);
      pgbuf_ordered_unfix_and_init (thread_p, *page_ptr, &crt_watcher);
    }
  else
    {
      assert (crt_watcher.pgptr == NULL);
    }
  /* Page was not removed. */
  return false;
}

/*
 * heap_vpid_next () - Find next page of heap
 *   return: NO_ERROR
 *   hfid(in): Object heap file identifier
 *   pgptr(in): Current page pointer
 *   next_vpid(in/out): Next volume-page identifier
 *
 * Note: Find the next page of heap file.
 */
int
heap_vpid_next (THREAD_ENTRY * thread_p, const HFID * hfid, PAGE_PTR pgptr, VPID * next_vpid)
{
  HEAP_CHAIN *chain;        /* Chain to next and prev page */
  HEAP_HDR_STATS *heap_hdr; /* Header of heap file */
  RECDES recdes;        /* Record descriptor to page header */
  int ret = NO_ERROR;

  (void) pgbuf_check_page_ptype (thread_p, pgptr, PAGE_HEAP);

  /* Get either the heap header or chain record */
  if (spage_get_record (thread_p, pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      /* Unable to get header/chain record for the given page */
      VPID_SET_NULL (next_vpid);
      ret = ER_FAILED;
    }
  else
    {
      pgbuf_get_vpid (pgptr, next_vpid);
      /* Is this the header page ? */
      if (next_vpid->pageid == hfid->hpgid && next_vpid->volid == hfid->vfid.volid)
    {
      heap_hdr = (HEAP_HDR_STATS *) recdes.data;
      *next_vpid = heap_hdr->next_vpid;
    }
      else
    {
      chain = (HEAP_CHAIN *) recdes.data;
      *next_vpid = chain->next_vpid;
    }
    }

  return ret;
}

/*
 * heap_vpid_prev () - Find previous page of heap
 *   return: NO_ERROR
 *   hfid(in): Object heap file identifier
 *   pgptr(in): Current page pointer
 *   prev_vpid(in/out): Previous volume-page identifier
 *
 * Note: Find the previous page of heap file.
 */
int
heap_vpid_prev (THREAD_ENTRY * thread_p, const HFID * hfid, PAGE_PTR pgptr, VPID * prev_vpid)
{
  HEAP_CHAIN *chain;        /* Chain to next and prev page */
  RECDES recdes;        /* Record descriptor to page header */
  int ret = NO_ERROR;

  (void) pgbuf_check_page_ptype (thread_p, pgptr, PAGE_HEAP);

  /* Get either the header or chain record */
  if (spage_get_record (thread_p, pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      /* Unable to get header/chain record for the given page */
      VPID_SET_NULL (prev_vpid);
      ret = ER_FAILED;
    }
  else
    {
      pgbuf_get_vpid (pgptr, prev_vpid);
      /* Is this the header page ? */
      if (prev_vpid->pageid == hfid->hpgid && prev_vpid->volid == hfid->vfid.volid)
    {
      VPID_SET_NULL (prev_vpid);
    }
      else
    {
      chain = (HEAP_CHAIN *) recdes.data;
      *prev_vpid = chain->prev_vpid;
    }
    }

  return ret;
}

/*
 * heap_manager_initialize () -
 *   return: NO_ERROR
 *
 * Note: Initialization process of the heap file module. Find the
 * maximum size of an object that can be inserted in the heap.
 * Objects that overpass this size are stored in overflow.
 */
int
heap_manager_initialize (void)
{
  int ret;

#define HEAP_MAX_FIRSTSLOTID_LENGTH (sizeof (HEAP_HDR_STATS))

  heap_Maxslotted_reclength = (spage_max_record_size () - HEAP_MAX_FIRSTSLOTID_LENGTH);
  heap_Slotted_overhead = spage_slot_size ();

  /* Initialize the class representation cache */
  ret = heap_chnguess_initialize ();
  if (ret != NO_ERROR)
    {
      return ret;
    }

  ret = heap_classrepr_initialize_cache ();
  if (ret != NO_ERROR)
    {
      return ret;
    }

  /* Initialize best space cache */
  ret = heap_stats_bestspace_initialize ();
  if (ret != NO_ERROR)
    {
      return ret;
    }

  /* Initialize class OID->HFID cache */
  ret = heap_initialize_hfid_table ();

  return ret;
}

/*
 * heap_manager_finalize () - Terminate the heap manager
 *   return: NO_ERROR
 * Note: Deallocate any cached structure.
 */
int
heap_manager_finalize (void)
{
  int ret;

  ret = heap_chnguess_finalize ();
  if (ret != NO_ERROR)
    {
      return ret;
    }

  ret = heap_classrepr_finalize_cache ();
  if (ret != NO_ERROR)
    {
      return ret;
    }

  ret = heap_stats_bestspace_finalize ();
  if (ret != NO_ERROR)
    {
      return ret;
    }

  heap_finalize_hfid_table ();

  return ret;
}

/*
 * heap_create_internal () - Create a heap file
 *   return: HFID * (hfid on success and NULL on failure)
 *   hfid(in/out): Object heap file identifier.
 *                 All fields in the identifier are set, except the volume
 *                 identifier which should have already been set by the caller.
 *   exp_npgs(in): Expected number of pages
 *   class_oid(in): OID of the class for which the heap will be created.
 *   reuse_oid(in): if true, the OIDs of deleted instances will be reused
 *
 * Note: Creates a heap file on the disk volume associated with
 * hfid->vfid->volid.
 *
 * A set of sectors is allocated to improve locality of the heap.
 * The number of sectors to allocate is estimated from the number
 * of expected pages. The maximum number of allocated sectors is
 * 25% of the total number of sectors in disk. When the number of
 * pages cannot be estimated, a negative value can be passed to
 * indicate so. In this case, no sectors are allocated. The
 * number of expected pages are not allocated at this moment,
 * they are allocated as needs arrives.
 */
static int
heap_create_internal (THREAD_ENTRY * thread_p, HFID * hfid, const OID * class_oid, const bool reuse_oid)
{
  HEAP_HDR_STATS heap_hdr;  /* Heap file header */
  VPID vpid;            /* Volume and page identifiers */
  RECDES recdes;        /* Record descriptor */
  LOG_DATA_ADDR addr_hdr;   /* Address of logging data */
  INT16 slotid;
  int sp_success;
  int i;
  FILE_DESCRIPTORS des;
  const FILE_TYPE file_type = reuse_oid ? FILE_HEAP_REUSE_SLOTS : FILE_HEAP;
  PAGE_TYPE ptype = PAGE_HEAP;
  OID null_oid = OID_INITIALIZER;

  int error_code = NO_ERROR;

  addr_hdr.pgptr = NULL;
  log_sysop_start (thread_p);

  if (class_oid == NULL)
    {
      class_oid = &null_oid;
    }
  memset (hfid, 0, sizeof (HFID));
  HFID_SET_NULL (hfid);

  memset (&des, 0, sizeof (des));

  if (prm_get_bool_value (PRM_ID_DONT_REUSE_HEAP_FILE) == false)
    {
      /* 
       * Try to reuse an already mark deleted heap file
       */

      error_code = file_tracker_reuse_heap (thread_p, class_oid, hfid);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto error;
    }

      if (!HFID_IS_NULL (hfid))
    {
      /* reuse heap file */
      if (heap_reuse (thread_p, hfid, class_oid, reuse_oid) == NULL)
        {
          ASSERT_ERROR_AND_SET (error_code);
          goto error;
        }
      error_code = heap_insert_hfid_for_class_oid (thread_p, class_oid, hfid, file_type);
      if (error_code != NO_ERROR)
        {
          /* could not cache */
          assert_release (false);
          goto error;
        }
      /* reuse successful */
      goto end;
    }
    }

  /* 
   * Create the unstructured file for the heap
   * Create the header for the heap file. The header is used to speed
   * up insertions of objects and to find some simple information about the
   * heap.
   * We do not initialize the page during the allocation since the file is
   * new, and the file is going to be removed in the event of a crash.
   */

  error_code = file_create_heap (thread_p, reuse_oid, class_oid, &hfid->vfid);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto error;
    }
  error_code = file_alloc_sticky_first_page (thread_p, &hfid->vfid, file_init_page_type, &ptype, &vpid,
                         &addr_hdr.pgptr);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto error;
    }
  if (vpid.volid != hfid->vfid.volid)
    {
      /* we got problems */
      assert_release (false);
      error_code = ER_FAILED;
      goto error;
    }
  if (addr_hdr.pgptr == NULL)
    {
      /* something went wrong, destroy the file, and return */
      assert_release (false);
      error_code = ER_FAILED;
      goto error;
    }

  hfid->hpgid = vpid.pageid;

  /* update file descriptor to include class and hfid */
  des.heap.class_oid = *class_oid;
  des.heap.hfid = *hfid;
  error_code = file_descriptor_update (thread_p, &hfid->vfid, &des);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto error;
    }

  error_code = heap_insert_hfid_for_class_oid (thread_p, class_oid, hfid, file_type);
  if (error_code != NO_ERROR)
    {
      /* Failed to cache HFID. */
      assert_release (false);
      goto error;
    }

  (void) heap_stats_del_bestspace_by_hfid (thread_p, hfid);

  pgbuf_set_page_ptype (thread_p, addr_hdr.pgptr, PAGE_HEAP);

  /* Initialize header page */
  spage_initialize (thread_p, addr_hdr.pgptr, heap_get_spage_type (), HEAP_MAX_ALIGN, SAFEGUARD_RVSPACE);

  /* Now insert header */
  memset (&heap_hdr, 0, sizeof (heap_hdr));
  heap_hdr.class_oid = *class_oid;
  VFID_SET_NULL (&heap_hdr.ovf_vfid);
  VPID_SET_NULL (&heap_hdr.next_vpid);

  heap_hdr.unfill_space = (int) ((float) DB_PAGESIZE * prm_get_float_value (PRM_ID_HF_UNFILL_FACTOR));

  heap_hdr.estimates.num_pages = 1;
  heap_hdr.estimates.num_recs = 0;
  heap_hdr.estimates.recs_sumlen = 0.0;

  heap_hdr.estimates.best[0].vpid.volid = hfid->vfid.volid;
  heap_hdr.estimates.best[0].vpid.pageid = hfid->hpgid;
  heap_hdr.estimates.best[0].freespace = spage_max_space_for_new_record (thread_p, addr_hdr.pgptr);

  heap_hdr.estimates.head = 1;
  for (i = heap_hdr.estimates.head; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      VPID_SET_NULL (&heap_hdr.estimates.best[i].vpid);
      heap_hdr.estimates.best[i].freespace = 0;
    }

  heap_hdr.estimates.num_high_best = 1;
  heap_hdr.estimates.num_other_high_best = 0;

  heap_hdr.estimates.num_second_best = 0;
  heap_hdr.estimates.head_second_best = 0;
  heap_hdr.estimates.tail_second_best = 0;
  heap_hdr.estimates.num_substitutions = 0;

  for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      VPID_SET_NULL (&heap_hdr.estimates.second_best[i]);
    }

  heap_hdr.estimates.last_vpid.volid = hfid->vfid.volid;
  heap_hdr.estimates.last_vpid.pageid = hfid->hpgid;

  heap_hdr.estimates.full_search_vpid.volid = hfid->vfid.volid;
  heap_hdr.estimates.full_search_vpid.pageid = hfid->hpgid;

  recdes.area_size = recdes.length = sizeof (HEAP_HDR_STATS);
  recdes.type = REC_HOME;
  recdes.data = (char *) &heap_hdr;

  sp_success = spage_insert (thread_p, addr_hdr.pgptr, &recdes, &slotid);
  if (sp_success != SP_SUCCESS || slotid != HEAP_HEADER_AND_CHAIN_SLOTID)
    {
      assert (false);
      /* something went wrong, destroy file and return error */
      if (sp_success != SP_SUCCESS)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNABLE_TO_CREATE_HEAP, 1,
          fileio_get_volume_label (hfid->vfid.volid, PEEK));
    }

      /* Free the page and release the lock */
      error_code = ER_HEAP_UNABLE_TO_CREATE_HEAP;
      goto error;
    }
  else
    {
      /* 
       * Don't need to log before image (undo) since file and pages of the heap
       * are deallocated during undo (abort).
       */
      addr_hdr.vfid = &hfid->vfid;
      addr_hdr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;
      log_append_redo_data (thread_p, RVHF_CREATE_HEADER, &addr_hdr, sizeof (heap_hdr), &heap_hdr);
      pgbuf_set_dirty (thread_p, addr_hdr.pgptr, FREE);
      addr_hdr.pgptr = NULL;
    }

end:
  assert (error_code == NO_ERROR);

  log_sysop_attach_to_outer (thread_p);
  vacuum_log_add_dropped_file (thread_p, &hfid->vfid, class_oid, VACUUM_LOG_ADD_DROPPED_FILE_UNDO);

  LOG_CS_ENTER (thread_p);
  logpb_flush_pages_direct (thread_p);
  LOG_CS_EXIT (thread_p);

  return NO_ERROR;

error:
  assert (error_code != NO_ERROR);

  if (addr_hdr.pgptr != NULL)
    {
      pgbuf_unfix_and_init (thread_p, addr_hdr.pgptr);
    }

  hfid->vfid.fileid = NULL_FILEID;
  hfid->hpgid = NULL_PAGEID;

  log_sysop_abort (thread_p);
  return error_code;
}

/*
 * heap_delete_all_page_records () -
 *   return: false if nothing is deleted, otherwise true
 *   vpid(in): the vpid of the page
 *   pgptr(in): PAGE_PTR to the page
 */
static bool
heap_delete_all_page_records (THREAD_ENTRY * thread_p, const VPID * vpid, PAGE_PTR pgptr)
{
  bool something_deleted = false;
  OID oid;
  RECDES recdes;

  assert (pgptr != NULL);
  assert (vpid != NULL);

  oid.volid = vpid->volid;
  oid.pageid = vpid->pageid;
  oid.slotid = NULL_SLOTID;

  while (true)
    {
      if (spage_next_record (pgptr, &oid.slotid, &recdes, PEEK) != S_SUCCESS)
    {
      break;
    }
      if (oid.slotid == HEAP_HEADER_AND_CHAIN_SLOTID)
    {
      continue;
    }
      (void) spage_delete (thread_p, pgptr, oid.slotid);
      something_deleted = true;
    }

  return something_deleted;
}

/*
 * heap_reinitialize_page () -
 *   return: NO_ERROR if succeed, otherwise error code
 *   pgptr(in): PAGE_PTR to the page
 *   is_header_page(in): true if the page is the header page
 */
static int
heap_reinitialize_page (THREAD_ENTRY * thread_p, PAGE_PTR pgptr, const bool is_header_page)
{
  HEAP_CHAIN tmp_chain;
  HEAP_HDR_STATS tmp_hdr_stats;
  PGSLOTID slotid = NULL_SLOTID;
  RECDES recdes;
  int error_code = NO_ERROR;

  if (spage_get_record (thread_p, pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      error_code = ER_GENERIC_ERROR;
      goto error_exit;
    }

  if (is_header_page)
    {
      assert (recdes.length == sizeof (HEAP_HDR_STATS));
      tmp_hdr_stats = *(HEAP_HDR_STATS *) recdes.data;
      recdes.data = (char *) &tmp_hdr_stats;
      recdes.area_size = recdes.length = sizeof (tmp_hdr_stats);
      recdes.type = REC_HOME;
    }
  else
    {
      assert (recdes.length == sizeof (HEAP_CHAIN));
      tmp_chain = *(HEAP_CHAIN *) recdes.data;
      recdes.data = (char *) &tmp_chain;
      recdes.area_size = recdes.length = sizeof (tmp_chain);
      recdes.type = REC_HOME;
    }

  (void) pgbuf_set_page_ptype (thread_p, pgptr, PAGE_HEAP);

  /* Initialize header page */
  spage_initialize (thread_p, pgptr, heap_get_spage_type (), HEAP_MAX_ALIGN, SAFEGUARD_RVSPACE);

  if (spage_insert (thread_p, pgptr, &recdes, &slotid) != SP_SUCCESS || slotid != HEAP_HEADER_AND_CHAIN_SLOTID)
    {
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      error_code = ER_GENERIC_ERROR;
      goto error_exit;
    }
  else
    {
      /* All is well and the page is now empty. */
    }

  return error_code;

error_exit:
  if (error_code == NO_ERROR)
    {
      error_code = ER_GENERIC_ERROR;
    }
  return error_code;
}

/*
 * heap_reuse () - Reuse a heap
 *   return: HFID * (hfid on success and NULL on failure)
 *   hfid(in): Object heap file identifier.
 *   class_oid(in): OID of the class for which the heap will be created.
 *
 * Note: Clean the given heap file so that it can be reused.
 * Note: The heap file must have been permanently marked as deleted.
 */
static const HFID *
heap_reuse (THREAD_ENTRY * thread_p, const HFID * hfid, const OID * class_oid, const bool reuse_oid)
{
  VPID vpid;            /* Volume and page identifiers */
  PAGE_PTR hdr_pgptr = NULL;    /* Page pointer to header page */
  PAGE_PTR pgptr = NULL;    /* Page pointer */
  LOG_DATA_ADDR addr;       /* Address of logging data */
  HEAP_HDR_STATS *heap_hdr = NULL;  /* Header of heap structure */
  HEAP_CHAIN *chain;        /* Chain to next and prev page */
  RECDES recdes;
  VPID last_vpid;
  int is_header_page;
  int npages = 0;
  int i;
  bool need_update;

  assert (class_oid != NULL);
  assert (!OID_ISNULL (class_oid));

  VPID_SET_NULL (&last_vpid);
  addr.vfid = &hfid->vfid;

  /* 
   * Read the header page.
   * We lock the header page in exclusive mode.
   */

  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;
  hdr_pgptr = pgbuf_fix (thread_p, &vpid, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_UNCONDITIONAL_LATCH);
  if (hdr_pgptr == NULL)
    {
      return NULL;
    }

  (void) pgbuf_check_page_ptype (thread_p, hdr_pgptr, PAGE_HEAP);

  /* 
   * Start scanning every page of the heap and removing the objects.
   * Note that, for normal heap files, the slot is not removed since we do not
   * know if the objects are pointed by some other objects in the database.
   * For reusable OID heap files we are certain there can be no references to
   * the objects so we can simply initialize the slotted page.
   */
  /* 
   * Note Because the objects of reusable OID heaps are not referenced,
   *      reusing such heaps provides no actual benefit. We might consider
   *      giving up the reuse heap mechanism for reusable OID heaps in the
   *      future.
   */

  while (!(VPID_ISNULL (&vpid)))
    {
      /* 
       * Fetch the page
       */
      pgptr = pgbuf_fix (thread_p, &vpid, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_UNCONDITIONAL_LATCH);
      if (pgptr == NULL)
    {
      goto error;
    }

      (void) pgbuf_check_page_ptype (thread_p, pgptr, PAGE_HEAP);

      is_header_page = (hdr_pgptr == pgptr) ? 1 : 0;

      /* 
       * Remove all the objects in this page
       */
      if (!reuse_oid)
    {
      (void) heap_delete_all_page_records (thread_p, &vpid, pgptr);

      addr.pgptr = pgptr;
      addr.offset = is_header_page;
      log_append_redo_data (thread_p, RVHF_REUSE_PAGE, &addr, sizeof (*class_oid), class_oid);
    }
      else
    {
      if (spage_number_of_slots (pgptr) > 1)
        {
          if (heap_reinitialize_page (thread_p, pgptr, is_header_page) != NO_ERROR)
        {
          goto error;
        }
        }

      addr.pgptr = pgptr;
      addr.offset = is_header_page;
      log_append_redo_data (thread_p, RVHF_REUSE_PAGE_REUSE_OID, &addr, sizeof (*class_oid), class_oid);
    }

      if (spage_get_record (thread_p, pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      goto error;
    }
      if (recdes.data == NULL)
    {
      goto error;
    }

      /* save new class oid in the page. it dirties the page. */
      if (is_header_page)
    {
      heap_hdr = (HEAP_HDR_STATS *) recdes.data;
      COPY_OID (&(heap_hdr->class_oid), class_oid);
    }
      else
    {
      chain = (HEAP_CHAIN *) recdes.data;
      COPY_OID (&(chain->class_oid), class_oid);
      chain->max_mvccid = MVCCID_NULL;
      chain->flags = 0;
      HEAP_PAGE_SET_VACUUM_STATUS (chain, HEAP_PAGE_VACUUM_NONE);
    }

      if (npages < HEAP_NUM_BEST_SPACESTATS)
    {
      heap_hdr->estimates.best[npages].vpid = vpid;
      heap_hdr->estimates.best[npages].freespace =
        spage_get_free_space_without_saving (thread_p, pgptr, &need_update);

    }

      if (prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES) > 0)
    {
      (void) heap_stats_add_bestspace (thread_p, hfid, &vpid, DB_PAGESIZE);
    }

      npages++;
      last_vpid = vpid;

      /* 
       * Find next page to scan and free the current page
       */
      if (heap_vpid_next (thread_p, hfid, pgptr, &vpid) != NO_ERROR)
    {
      goto error;
    }

      pgbuf_set_dirty (thread_p, pgptr, FREE);
      pgptr = NULL;
    }

  /* 
   * Reset the statistics. Set statistics for insertion back to first page
   * and reset unfill space according to new parameters
   */
  VFID_SET_NULL (&heap_hdr->ovf_vfid);
  heap_hdr->unfill_space = (int) ((float) DB_PAGESIZE * prm_get_float_value (PRM_ID_HF_UNFILL_FACTOR));
  heap_hdr->estimates.num_pages = npages;
  heap_hdr->estimates.num_recs = 0;
  heap_hdr->estimates.recs_sumlen = 0.0;

  if (npages < HEAP_NUM_BEST_SPACESTATS)
    {
      heap_hdr->estimates.num_high_best = npages;
      heap_hdr->estimates.num_other_high_best = 0;
    }
  else
    {
      heap_hdr->estimates.num_high_best = HEAP_NUM_BEST_SPACESTATS;
      heap_hdr->estimates.num_other_high_best = npages - HEAP_NUM_BEST_SPACESTATS;
    }

  heap_hdr->estimates.head = 0;
  for (i = npages; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      VPID_SET_NULL (&heap_hdr->estimates.best[i].vpid);
      heap_hdr->estimates.best[i].freespace = 0;
    }

  heap_hdr->estimates.last_vpid = last_vpid;

  addr.pgptr = hdr_pgptr;
  addr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;
  log_append_redo_data (thread_p, RVHF_STATS, &addr, sizeof (*heap_hdr), heap_hdr);
  pgbuf_set_dirty (thread_p, hdr_pgptr, FREE);
  hdr_pgptr = NULL;

  return hfid;

error:
  if (pgptr != NULL)
    {
      pgbuf_unfix_and_init (thread_p, pgptr);
    }
  if (hdr_pgptr != NULL)
    {
      pgbuf_unfix_and_init (thread_p, hdr_pgptr);
    }

  return NULL;
}

#if defined(CUBRID_DEBUG)
/*
 * heap_hfid_isvalid () -
 *   return:
 *   hfid(in):
 */
static DISK_ISVALID
heap_hfid_isvalid (HFID * hfid)
{
  DISK_ISVALID valid_pg = DISK_VALID;

  if (hfid == NULL || HFID_IS_NULL (hfid))
    {
      return DISK_INVALID;
    }

  valid_pg = disk_is_page_sector_reserved (hfid->vfid.volid, hfid->vfid.fileid);
  if (valid_pg == DISK_VALID)
    {
      valid_pg = disk_is_page_sector_reserved (hfid->vfid.volid, hfid->hpgid);
    }

  return valid_pg;
}

/*
 * heap_scanrange_isvalid () -
 *   return:
 *   scan_range(in):
 */
static DISK_ISVALID
heap_scanrange_isvalid (HEAP_SCANRANGE * scan_range)
{
  DISK_ISVALID valid_pg = DISK_INVALID;

  if (scan_range != NULL)
    {
      valid_pg = heap_hfid_isvalid (&scan_range->scan_cache.hfid);
    }

  if (valid_pg != DISK_VALID)
    {
      if (valid_pg != DISK_ERROR)
    {
      er_log_debug (ARG_FILE_LINE, " ** SYSTEM ERROR scanrange has not been initialized");
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
    }
    }

  return valid_pg;
}
#endif /* CUBRID_DEBUG */

/*
 * xheap_create () - Create a heap file
 *   return: int
 *   hfid(in/out): Object heap file identifier.
 *                 All fields in the identifier are set, except the volume
 *                 identifier which should have already been set by the caller.
 *   class_oid(in): OID of the class for which the heap will be created.
 *   reuse_oid(int):
 *
 * Note: Creates an object heap file on the disk volume associated with
 * hfid->vfid->volid.
 */
int
xheap_create (THREAD_ENTRY * thread_p, HFID * hfid, const OID * class_oid, bool reuse_oid)
{
  return heap_create_internal (thread_p, hfid, class_oid, reuse_oid);
}

/*
 * xheap_destroy () - Destroy a heap file
 *   return: int
 *   hfid(in): Object heap file identifier.
 *   class_oid(in):
 *
 * Note: Destroy the heap file associated with the given heap identifier.
 */
int
xheap_destroy (THREAD_ENTRY * thread_p, const HFID * hfid, const OID * class_oid)
{
  VFID vfid;
  LOG_DATA_ADDR addr;

  vacuum_log_add_dropped_file (thread_p, &hfid->vfid, class_oid, VACUUM_LOG_ADD_DROPPED_FILE_POSTPONE);

  addr.vfid = NULL;
  addr.pgptr = NULL;
  addr.offset = -1;
  if (heap_ovf_find_vfid (thread_p, hfid, &vfid, false, PGBUF_UNCONDITIONAL_LATCH) != NULL)
    {
      file_postpone_destroy (thread_p, &vfid);
    }

  file_postpone_destroy (thread_p, &hfid->vfid);

  (void) heap_stats_del_bestspace_by_hfid (thread_p, hfid);

  return NO_ERROR;
}

/*
 * xheap_destroy_newly_created () - Destroy heap if it is a newly created heap
 *   return: NO_ERROR
 *   hfid(in): Object heap file identifier.
 *   class_oid(in): class OID
 *
 * Note: Destroy the heap file associated with the given heap
 * identifier if it is a newly created heap file.
 */
int
xheap_destroy_newly_created (THREAD_ENTRY * thread_p, const HFID * hfid, const OID * class_oid)
{
  VFID vfid;
  FILE_TYPE file_type;
  int ret;
  LOG_DATA_ADDR addr = LOG_DATA_ADDR_INITIALIZER;

  ret = file_get_type (thread_p, &hfid->vfid, &file_type);
  if (ret != NO_ERROR)
    {
      ASSERT_ERROR ();
      return ret;
    }
  if (file_type == FILE_HEAP_REUSE_SLOTS)
    {
      ret = xheap_destroy (thread_p, hfid, class_oid);
      return ret;
    }

  vacuum_log_add_dropped_file (thread_p, &hfid->vfid, NULL, VACUUM_LOG_ADD_DROPPED_FILE_POSTPONE);

  if (heap_ovf_find_vfid (thread_p, hfid, &vfid, false, PGBUF_UNCONDITIONAL_LATCH) != NULL)
    {
      file_postpone_destroy (thread_p, &vfid);
    }

  log_append_postpone (thread_p, RVHF_MARK_DELETED, &addr, sizeof (hfid->vfid), &hfid->vfid);

  (void) heap_stats_del_bestspace_by_hfid (thread_p, hfid);

  return ret;
}

/*
 * heap_rv_mark_deleted_on_undo () - mark heap file as deleted on undo
 *
 * return        : error code
 * thread_p (in) : thread entry
 * rcv (in)      : recovery data
 */
int
heap_rv_mark_deleted_on_undo (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  int error_code = file_rv_tracker_mark_heap_deleted (thread_p, rcv, true);
  if (error_code != NO_ERROR)
    {
      assert_release (false);
    }
  return error_code;
}

/*
 * heap_rv_mark_deleted_on_postpone () - mark heap file as deleted on postpone
 *
 * return        : error code
 * thread_p (in) : thread entry
 * rcv (in)      : recovery data
 */
int
heap_rv_mark_deleted_on_postpone (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  int error_code = file_rv_tracker_mark_heap_deleted (thread_p, rcv, false);
  if (error_code != NO_ERROR)
    {
      assert_release (false);
    }
  return error_code;
}

/*
 * heap_assign_address () - Assign a new location
 *   return: NO_ERROR / ER_FAILED
 *   hfid(in): Object heap file identifier
 *   class_oid(in): class identifier
 *   oid(out): Object identifier.
 *   expected_length(in): Expected length
 *
 * Note: Assign an OID to an object and reserve the expected length for
 * the object. The following rules are observed for the expected length.
 *              1. A negative value is passed when only an approximation of
 *                 the length of the object is known. This approximation is
 *                 taken as the minimal length by this module. This case is
 *                 used when the transformer module (tfcl) skips some fileds
 *                 while walking through the object to find out its length.
 *                 a) Heap manager find the average length of objects in the
 *                    heap.
 *                    If the average length > abs(expected_length)
 *                    The average length is used instead
 *              2. A zero value, heap manager uses the average length of the
 *                 objects in the heap.
 *              3. If length is larger than one page, the size of an OID is
 *                 used since the object is going to be stored in overflow
 *              4. If length is > 0 and smaller than OID_SIZE
 *                 OID_SIZE is used as the expected length.
 */
int
heap_assign_address (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, OID * oid, int expected_length)
{
  HEAP_OPERATION_CONTEXT insert_context;
  RECDES recdes;
  int rc;

  if (expected_length <= 0)
    {
      recdes.length = heap_estimate_avg_length (thread_p, hfid);
      if (recdes.length > (-expected_length))
    {
      expected_length = recdes.length;
    }
      else
    {
      expected_length = -expected_length;
    }
    }

  /* 
   * Use the expected length only when it is larger than the size of an OID
   * and it is smaller than the maximum size of an object that can be stored
   * in the primary area (no in overflow). In any other case, use the the size
   * of an OID as the length.
   */

  recdes.length =
    ((expected_length > SSIZEOF (OID) && !heap_is_big_length (expected_length)) ? expected_length : SSIZEOF (OID));

  recdes.data = NULL;
  recdes.type = REC_ASSIGN_ADDRESS;

  /* create context */
  heap_create_insert_context (&insert_context, (HFID *) hfid, class_oid, &recdes, NULL);

  /* insert */
  rc = heap_insert_logical (thread_p, &insert_context);
  if (rc != NO_ERROR)
    {
      return rc;
    }

  /* get result and exit */
  COPY_OID (oid, &insert_context.res_oid);
  return NO_ERROR;
}

/*
 * heap_flush () - Flush all dirty pages where the object resides
 *   return:
 *   oid(in): Object identifier
 *
 * Note: Flush all dirty pages where the object resides.
 */
void
heap_flush (THREAD_ENTRY * thread_p, const OID * oid)
{
  VPID vpid;            /* Volume and page identifiers */
  PAGE_PTR pgptr = NULL;    /* Page pointer */
  INT16 type;
  OID forward_oid;
  RECDES forward_recdes;
  int ret = NO_ERROR;

  if (HEAP_ISVALID_OID (thread_p, oid) != DISK_VALID)
    {
      return;
    }

  /* 
   * Lock and fetch the page where the object is stored
   */
  vpid.volid = oid->volid;
  vpid.pageid = oid->pageid;
  pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, S_LOCK, NULL, NULL);
  if (pgptr == NULL)
    {
      if (er_errid () == ER_PB_BAD_PAGEID)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, oid->volid, oid->pageid, oid->slotid);
    }
      /* something went wrong, return */
      return;
    }

  (void) pgbuf_check_page_ptype (thread_p, pgptr, PAGE_HEAP);

  type = spage_get_record_type (pgptr, oid->slotid);
  if (type == REC_UNKNOWN)
    {
      goto end;
    }

  /* If this page is dirty flush it */
  (void) pgbuf_flush_with_wal (thread_p, pgptr);

  switch (type)
    {
    case REC_RELOCATION:
      /* 
       * The object stored on the page is a relocation record. The relocation
       * record is used as a map to find the actual location of the content of
       * the object.
       */

      forward_recdes.data = (char *) &forward_oid;
      forward_recdes.area_size = OR_OID_SIZE;

      if (spage_get_record (thread_p, pgptr, oid->slotid, &forward_recdes, COPY) != S_SUCCESS)
    {
      /* Unable to get relocation record of the object */
      goto end;
    }
      pgbuf_unfix_and_init (thread_p, pgptr);

      /* Fetch the new home page */
      vpid.volid = forward_oid.volid;
      vpid.pageid = forward_oid.pageid;

      pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, S_LOCK, NULL, NULL);
      if (pgptr == NULL)
    {
      if (er_errid () == ER_PB_BAD_PAGEID)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, forward_oid.volid,
              forward_oid.pageid, forward_oid.slotid);
        }

      return;
    }

      (void) pgbuf_check_page_ptype (thread_p, pgptr, PAGE_HEAP);

      (void) pgbuf_flush_with_wal (thread_p, pgptr);
      break;

    case REC_BIGONE:
      /* 
       * The object stored in the heap page is a relocation_overflow record,
       * get the overflow address of the object
       */
      forward_recdes.data = (char *) &forward_oid;
      forward_recdes.area_size = OR_OID_SIZE;

      if (spage_get_record (thread_p, pgptr, oid->slotid, &forward_recdes, COPY) != S_SUCCESS)
    {
      /* Unable to peek overflow address of multipage object */
      goto end;
    }
      pgbuf_unfix_and_init (thread_p, pgptr);
      ret = heap_ovf_flush (thread_p, &forward_oid);
      break;

    case REC_ASSIGN_ADDRESS:
    case REC_HOME:
    case REC_NEWHOME:
    case REC_MARKDELETED:
    case REC_DELETED_WILL_REUSE:
    default:
      break;
    }

end:
  if (pgptr != NULL)
    {
      pgbuf_unfix_and_init (thread_p, pgptr);
    }
}

/*
 * xheap_reclaim_addresses () - Reclaim addresses/OIDs and delete empty pages
 *   return: NO_ERROR
 *   hfid(in): Heap file identifier
 *
 * Note: Reclaim the addresses (OIDs) of deleted objects of the given heap and
 *       delete all the heap pages that are left empty.
 *
 *       This function can be called:
 *    a: When there are no more references to deleted objects of the given
 *       heap. This happens during offline compactdb execution after all the
 *       classes in the schema have been processed by the process_class ()
 *       function that sets the references to deleted objects to NULL.
 *    b: When we are sure there can be no references to any object of the
 *       associated class. This happens during online compactdb execution when
 *       all the classes in the schema are checked to see if can they point to
 *       instances of the current class by checking all their atributes'
 *       domains.
 *
 *       If references to deleted objects were nulled by the current
 *       transaction some recovery problems may happen in the case of a crash
 *       since the reclaiming of the addresses is done without logging (or
 *       very little one) and thus it cannot be fully undone. Some logging is
 *       done to make sure that media recovery will not be impacted. This was
 *       done to avoid a lot of unneeded logging. Thus, if the caller was
 *       setting references to deleted objects to NULL, the caller must commit
 *       his transaction before this function is invoked.
 *
 *      This function must be run:
 *   a: offline, that is, when the user is the only one using the database
 *      system.
 *   b: online while holding an exclusive lock on the associated class.
 */
int
xheap_reclaim_addresses (THREAD_ENTRY * thread_p, const HFID * hfid)
{
  VPID vpid;
  VPID prv_vpid;
  int best, i;
  HEAP_HDR_STATS initial_heap_hdr;
  HEAP_HDR_STATS heap_hdr;
  RECDES hdr_recdes;
  LOG_DATA_ADDR addr;
  int ret = NO_ERROR;
  int free_space;
  int npages, nrecords, rec_length;
  bool need_update;
  PGBUF_WATCHER hdr_page_watcher;
  PGBUF_WATCHER curr_page_watcher;

  PGBUF_INIT_WATCHER (&hdr_page_watcher, PGBUF_ORDERED_HEAP_HDR, hfid);
  PGBUF_INIT_WATCHER (&curr_page_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  addr.vfid = &hfid->vfid;
  addr.pgptr = NULL;
  addr.offset = 0;

  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;

  ret = pgbuf_ordered_fix (thread_p, &vpid, OLD_PAGE, PGBUF_LATCH_WRITE, &hdr_page_watcher);
  if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }

  (void) pgbuf_check_page_ptype (thread_p, hdr_page_watcher.pgptr, PAGE_HEAP);

  hdr_recdes.data = (char *) &heap_hdr;
  hdr_recdes.area_size = sizeof (heap_hdr);

  if (spage_get_record (thread_p, hdr_page_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &hdr_recdes, COPY) != S_SUCCESS)
    {
      goto exit_on_error;
    }
  prv_vpid = heap_hdr.estimates.last_vpid;

  /* Copy the header to memory.. so we can log the changes */
  memcpy (&initial_heap_hdr, hdr_recdes.data, sizeof (initial_heap_hdr));

  /* 
   * Initialize best estimates
   */
  heap_hdr.estimates.num_pages = 0;
  heap_hdr.estimates.num_recs = 0;
  heap_hdr.estimates.recs_sumlen = 0.0;
  heap_hdr.estimates.num_high_best = 0;
  heap_hdr.estimates.num_other_high_best = 0;
  heap_hdr.estimates.head = 0;

  for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      VPID_SET_NULL (&heap_hdr.estimates.best[i].vpid);
      heap_hdr.estimates.best[0].freespace = 0;
    }

  /* Initialize second best estimates */
  heap_hdr.estimates.num_second_best = 0;
  heap_hdr.estimates.head_second_best = 0;
  heap_hdr.estimates.tail_second_best = 0;
  heap_hdr.estimates.num_substitutions = 0;

  for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      VPID_SET_NULL (&heap_hdr.estimates.second_best[i]);
    }

  /* initialize full_search_vpid */
  heap_hdr.estimates.full_search_vpid.volid = hfid->vfid.volid;
  heap_hdr.estimates.full_search_vpid.pageid = hfid->hpgid;

  best = 0;

  while (!(VPID_ISNULL (&prv_vpid)))
    {
      vpid = prv_vpid;
      curr_page_watcher.pgptr =
    heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, X_LOCK, NULL, &curr_page_watcher);
      if (curr_page_watcher.pgptr == NULL)
    {
      goto exit_on_error;
    }

      (void) pgbuf_check_page_ptype (thread_p, curr_page_watcher.pgptr, PAGE_HEAP);

      if (heap_vpid_prev (thread_p, hfid, curr_page_watcher.pgptr, &prv_vpid) != NO_ERROR)
    {
      pgbuf_ordered_unfix (thread_p, &curr_page_watcher);

      goto exit_on_error;
    }

      /* 
       * Are there any objects in this page ?
       * Compare against > 1 since every heap page contains a header record
       * (heap header or chain).
       */

      if (spage_number_of_records (curr_page_watcher.pgptr) > 1
      || (vpid.pageid == hfid->hpgid && vpid.volid == hfid->vfid.volid))
    {
      if (spage_reclaim (thread_p, curr_page_watcher.pgptr) == true)
        {
          addr.pgptr = curr_page_watcher.pgptr;
          /* 
           * If this function is called correctly (see the notes in the
           * header comment about the preconditions) we can skip the
           * logging of spage_reclaim (). Logging for REDO would add many
           * log records for any compactdb operation and would only
           * benefit the infrequent scenario of compactdb operations that
           * crash right at the end. UNDO operations are not absolutely
           * required because the deleted OIDs should be unreferenced
           * anyway; there should be no harm in reusing them. Basically,
           * since the call to spage_reclaim () should leave the database
           * logically unmodified, neither REDO nor UNDO are required.
           */
          log_skip_logging (thread_p, &addr);
          pgbuf_set_dirty (thread_p, curr_page_watcher.pgptr, DONT_FREE);
        }
    }

      /* 
       * Throw away the page if it doesn't contain any object. The header of
       * the heap cannot be thrown.
       */

      if (!(vpid.pageid == hfid->hpgid && vpid.volid == hfid->vfid.volid)
      && spage_number_of_records (curr_page_watcher.pgptr) <= 1
      /* Is any vacuum required? */
      && vacuum_is_mvccid_vacuumed (heap_page_get_max_mvccid (thread_p, curr_page_watcher.pgptr)))
    {
      /* 
       * This page can be thrown away
       */
      pgbuf_ordered_unfix (thread_p, &curr_page_watcher);
      if (heap_vpid_remove (thread_p, hfid, &heap_hdr, &vpid) == NULL)
        {
          goto exit_on_error;
        }
      vacuum_er_log (VACUUM_ER_LOG_HEAP, "Compactdb removed page %d|%d from heap file (%d, %d|%d).\n",
             vpid.volid, vpid.pageid, hfid->hpgid, hfid->vfid.volid, hfid->vfid.fileid);
    }
      else
    {
      spage_collect_statistics (curr_page_watcher.pgptr, &npages, &nrecords, &rec_length);

      heap_hdr.estimates.num_pages += npages;
      heap_hdr.estimates.num_recs += nrecords;
      heap_hdr.estimates.recs_sumlen += rec_length;

      free_space = spage_get_free_space_without_saving (thread_p, curr_page_watcher.pgptr, &need_update);

      if (free_space > HEAP_DROP_FREE_SPACE)
        {
          if (best < HEAP_NUM_BEST_SPACESTATS)
        {
          heap_hdr.estimates.best[best].vpid = vpid;
          heap_hdr.estimates.best[best].freespace = free_space;
          best++;
        }
          else
        {
          heap_hdr.estimates.num_other_high_best++;
          heap_stats_put_second_best (&heap_hdr, &vpid);
        }

          if (prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES) > 0)
        {
          (void) heap_stats_add_bestspace (thread_p, hfid, &vpid, free_space);
        }
        }

      pgbuf_ordered_unfix (thread_p, &curr_page_watcher);
    }
    }

  heap_hdr.estimates.num_high_best = best;
  /* 
   * Set the rest of the statistics to NULL
   */
  for (; best < HEAP_NUM_BEST_SPACESTATS; best++)
    {
      VPID_SET_NULL (&heap_hdr.estimates.best[best].vpid);
      heap_hdr.estimates.best[best].freespace = 0;
    }

  /* Log the desired changes.. and then change the header We need to log the header changes in order to always benefit
   * from the updated statistics and in order to avoid referencing deleted pages in the statistics. */
  addr.pgptr = hdr_page_watcher.pgptr;
  addr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;
  log_append_undoredo_data (thread_p, RVHF_STATS, &addr, sizeof (HEAP_HDR_STATS), sizeof (HEAP_HDR_STATS),
                &initial_heap_hdr, hdr_recdes.data);

  /* Now update the statistics */
  if (spage_update (thread_p, hdr_page_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &hdr_recdes) != SP_SUCCESS)
    {
      goto exit_on_error;
    }

  pgbuf_ordered_set_dirty_and_free (thread_p, &hdr_page_watcher);

  return ret;

exit_on_error:

  if (hdr_page_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &hdr_page_watcher);
    }

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_ovf_find_vfid () - Find overflow file identifier
 *   return: ovf_vfid or NULL
 *   hfid(in): Object heap file identifier
 *   ovf_vfid(in/out): Overflow file identifier.
 *   docreate(in): true/false. If true and the overflow file does not
 *                 exist, it is created.
 *
 * Note: Find overflow file identifier. If the overflow file does not
 * exist, it may be created depending of the value of argument create.
 */
VFID *
heap_ovf_find_vfid (THREAD_ENTRY * thread_p, const HFID * hfid, VFID * ovf_vfid, bool docreate,
            PGBUF_LATCH_CONDITION latch_cond)
{
  HEAP_HDR_STATS *heap_hdr; /* Header of heap structure */
  LOG_DATA_ADDR addr_hdr;   /* Address of logging data */
  VPID vpid;            /* Page-volume identifier */
  RECDES hdr_recdes;        /* Header record descriptor */
  PGBUF_LATCH_MODE mode;

  addr_hdr.vfid = &hfid->vfid;
  addr_hdr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;

  /* Read the header page */
  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;

  mode = (docreate == true ? PGBUF_LATCH_WRITE : PGBUF_LATCH_READ);
  addr_hdr.pgptr = pgbuf_fix (thread_p, &vpid, OLD_PAGE, mode, latch_cond);
  if (addr_hdr.pgptr == NULL)
    {
      /* something went wrong, return */
      return NULL;
    }

  (void) pgbuf_check_page_ptype (thread_p, addr_hdr.pgptr, PAGE_HEAP);

  /* Peek the header record */

  if (spage_get_record (thread_p, addr_hdr.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &hdr_recdes, PEEK) != S_SUCCESS)
    {
      pgbuf_unfix_and_init (thread_p, addr_hdr.pgptr);
      return NULL;
    }

  heap_hdr = (HEAP_HDR_STATS *) hdr_recdes.data;
  if (VFID_ISNULL (&heap_hdr->ovf_vfid))
    {
      if (docreate == true)
    {
      FILE_DESCRIPTORS des;
      /* Create the overflow file. Try to create the overflow file in the same volume where the heap was defined */

      /* START A TOP SYSTEM OPERATION */
      log_sysop_start (thread_p);

      /* Initialize description of overflow heap file */
      memset (&des, 0, sizeof (des));
      HFID_COPY (&des.heap_overflow.hfid, hfid);
      des.heap_overflow.class_oid = heap_hdr->class_oid;
      if (file_create_with_npages (thread_p, FILE_MULTIPAGE_OBJECT_HEAP, 1, &des, ovf_vfid) == NO_ERROR)
        {
          /* Log undo, then redo */
          log_append_undo_data (thread_p, RVHF_STATS, &addr_hdr, sizeof (*heap_hdr), heap_hdr);
          VFID_COPY (&heap_hdr->ovf_vfid, ovf_vfid);
          log_append_redo_data (thread_p, RVHF_STATS, &addr_hdr, sizeof (*heap_hdr), heap_hdr);
          pgbuf_set_dirty (thread_p, addr_hdr.pgptr, DONT_FREE);

          log_sysop_commit (thread_p);
        }
      else
        {
          log_sysop_abort (thread_p);
          ovf_vfid = NULL;
        }
    }
      else
    {
      ovf_vfid = NULL;
    }
    }
  else
    {
      VFID_COPY (ovf_vfid, &heap_hdr->ovf_vfid);
    }

  pgbuf_unfix_and_init (thread_p, addr_hdr.pgptr);

  return ovf_vfid;
}

/*
 * heap_ovf_insert () - Insert the content of a multipage object in overflow
 *   return: OID *(ovf_oid on success or NULL on failure)
 *   hfid(in): Object heap file identifier
 *   ovf_oid(in/out): Overflow address
 *   recdes(in): Record descriptor
 *
 * Note: Insert the content of a multipage object in overflow.
 */
static OID *
heap_ovf_insert (THREAD_ENTRY * thread_p, const HFID * hfid, OID * ovf_oid, RECDES * recdes)
{
  VFID ovf_vfid;
  VPID ovf_vpid;        /* Address of overflow insertion */

  if (heap_ovf_find_vfid (thread_p, hfid, &ovf_vfid, true, PGBUF_UNCONDITIONAL_LATCH) == NULL
      || overflow_insert (thread_p, &ovf_vfid, &ovf_vpid, recdes, FILE_MULTIPAGE_OBJECT_HEAP) != NO_ERROR)
    {
      return NULL;
    }

  ovf_oid->pageid = ovf_vpid.pageid;
  ovf_oid->volid = ovf_vpid.volid;
  ovf_oid->slotid = NULL_SLOTID;    /* Irrelevant */

  return ovf_oid;
}

/*
 * heap_ovf_update () - Update the content of a multipage object
 *   return: OID *(ovf_oid on success or NULL on failure)
 *   hfid(in): Object heap file identifier
 *   ovf_oid(in): Overflow address
 *   recdes(in): Record descriptor
 *
 * Note: Update the content of a multipage object.
 */
static const OID *
heap_ovf_update (THREAD_ENTRY * thread_p, const HFID * hfid, const OID * ovf_oid, RECDES * recdes)
{
  VFID ovf_vfid;
  VPID ovf_vpid;

  if (heap_ovf_find_vfid (thread_p, hfid, &ovf_vfid, false, PGBUF_UNCONDITIONAL_LATCH) == NULL)
    {
      return NULL;
    }

  ovf_vpid.pageid = ovf_oid->pageid;
  ovf_vpid.volid = ovf_oid->volid;

  if (overflow_update (thread_p, &ovf_vfid, &ovf_vpid, recdes, FILE_MULTIPAGE_OBJECT_HEAP) != NO_ERROR)
    {
      ASSERT_ERROR ();
      return NULL;
    }
  else
    {
      return ovf_oid;
    }
}

/*
 * heap_ovf_delete () - Delete the content of a multipage object
 *   return: OID *(ovf_oid on success or NULL on failure)
 *   hfid(in): Object heap file identifier
 *   ovf_oid(in): Overflow address
 *   ovf_vfid_p(in): Overflow file identifier. If given argument is NULL,
 *           it must be obtained from heap file header.
 *
 * Note: Delete the content of a multipage object.
 */
const OID *
heap_ovf_delete (THREAD_ENTRY * thread_p, const HFID * hfid, const OID * ovf_oid, VFID * ovf_vfid_p)
{
  VFID ovf_vfid;
  VPID ovf_vpid;

  if (ovf_vfid_p == NULL || VFID_ISNULL (ovf_vfid_p))
    {
      /* Get overflow file VFID from heap file header. */
      ovf_vfid_p = (ovf_vfid_p != NULL) ? ovf_vfid_p : &ovf_vfid;
      if (heap_ovf_find_vfid (thread_p, hfid, ovf_vfid_p, false, PGBUF_UNCONDITIONAL_LATCH) == NULL)
    {
      return NULL;
    }
    }

  ovf_vpid.pageid = ovf_oid->pageid;
  ovf_vpid.volid = ovf_oid->volid;

  if (overflow_delete (thread_p, ovf_vfid_p, &ovf_vpid) == NULL)
    {
      return NULL;
    }
  else
    {
      return ovf_oid;
    }

}

/*
 * heap_ovf_flush () - Flush all overflow dirty pages where the object resides
 *   return: NO_ERROR
 *   ovf_oid(in): Overflow address
 *
 * Note: Flush all overflow dirty pages where the object resides.
 */
static int
heap_ovf_flush (THREAD_ENTRY * thread_p, const OID * ovf_oid)
{
  VPID ovf_vpid;

  ovf_vpid.pageid = ovf_oid->pageid;
  ovf_vpid.volid = ovf_oid->volid;
  overflow_flush (thread_p, &ovf_vpid);

  return NO_ERROR;
}

/*
 * heap_ovf_get_length () - Find length of overflow object
 *   return: length
 *   ovf_oid(in): Overflow address
 *
 * Note: The length of the content of a multipage object associated
 * with the given overflow address is returned. In the case of
 * any error, -1 is returned.
 */
static int
heap_ovf_get_length (THREAD_ENTRY * thread_p, const OID * ovf_oid)
{
  VPID ovf_vpid;

  ovf_vpid.pageid = ovf_oid->pageid;
  ovf_vpid.volid = ovf_oid->volid;

  return overflow_get_length (thread_p, &ovf_vpid);
}

/*
 * heap_ovf_get () - get/retrieve the content of a multipage object from overflow
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_DOESNT_FIT, S_END)
 *   ovf_oid(in): Overflow address
 *   recdes(in): Record descriptor
 *   chn(in):
 *
 * Note: The content of a multipage object associated with the given
 * overflow address(oid) is placed into the area pointed to by
 * the record descriptor. If the content of the object does not
 * fit in such an area (i.e., recdes->area_size), an error is
 * returned and a hint of its length is returned as a negative
 * value in recdes->length. The length of the retrieved object is
 * set in the the record descriptor (i.e., recdes->length).
 */
static SCAN_CODE
heap_ovf_get (THREAD_ENTRY * thread_p, const OID * ovf_oid, RECDES * recdes, int chn, MVCC_SNAPSHOT * mvcc_snapshot)
{
  VPID ovf_vpid;
  int rest_length;
  SCAN_CODE scan;

  ovf_vpid.pageid = ovf_oid->pageid;
  ovf_vpid.volid = ovf_oid->volid;

  if (chn != NULL_CHN)
    {
      /* 
       * This assumes that most of the time, we have the right cache coherency
       * number and that it is expensive to copy the overflow object to be
       * thrown most of the time. Thus, it is OK to do some extra page look up
       * when failures (it should be OK since the overflow page should be
       * already in the page buffer pool.
       */

      scan = overflow_get_nbytes (thread_p, &ovf_vpid, recdes, 0, OR_MVCC_MAX_HEADER_SIZE, &rest_length, mvcc_snapshot);
      if (scan == S_SUCCESS && chn == or_chn (recdes))
    {
      return S_SUCCESS_CHN_UPTODATE;
    }
    }
  scan = overflow_get (thread_p, &ovf_vpid, recdes, mvcc_snapshot);

  return scan;
}

/*
 * heap_ovf_get_capacity () - Find space consumed oveflow object
 *   return: NO_ERROR
 *   ovf_oid(in): Overflow address
 *   ovf_len(out): Length of overflow object
 *   ovf_num_pages(out): Total number of overflow pages
 *   ovf_overhead(out): System overhead for overflow record
 *   ovf_free_space(out): Free space for exapnsion of the overflow rec
 *
 * Note: Find the current storage facts/capacity of given overflow rec
 */
static int
heap_ovf_get_capacity (THREAD_ENTRY * thread_p, const OID * ovf_oid, int *ovf_len, int *ovf_num_pages,
               int *ovf_overhead, int *ovf_free_space)
{
  VPID ovf_vpid;

  ovf_vpid.pageid = ovf_oid->pageid;
  ovf_vpid.volid = ovf_oid->volid;

  return overflow_get_capacity (thread_p, &ovf_vpid, ovf_len, ovf_num_pages, ovf_overhead, ovf_free_space);
}

/*
 * heap_scancache_check_with_hfid () - Check if scancache is on provided HFID
 *                     and reinitialize it otherwise
 *   thread_p(in): thread entry
 *   hfid(in): heap file identifier to check the scancache against
 *   scan_cache(in/out): pointer to scancache pointer
 *   returns: error code or NO_ERROR
 *
 * NOTE: Function may alter the scan cache address. Caller must make sure it
 *       doesn't pass it's only reference to the object OR it is not the owner
 *       of the object.
 * NOTE: Function may alter the members of (*scan_cache).
 */
static int
heap_scancache_check_with_hfid (THREAD_ENTRY * thread_p, HFID * hfid, OID * class_oid, HEAP_SCANCACHE ** scan_cache)
{
  if (*scan_cache != NULL)
    {
      if ((*scan_cache)->debug_initpattern != HEAP_DEBUG_SCANCACHE_INITPATTERN)
    {
      er_log_debug (ARG_FILE_LINE, "heap_insert: Your scancache is not initialized");
      *scan_cache = NULL;
    }
      else if (!HFID_EQ (&(*scan_cache)->node.hfid, hfid) || OID_ISNULL (&(*scan_cache)->node.class_oid))
    {
      int r;

      /* scancache is not on our heap file, reinitialize it */
      /* this is a very dangerous thing to do and is very risky. the caller may have done a big mistake.
       * we could use it as backup for release run, but we should catch it on debug.
       * todo: add assert (false); here
       */
      r = heap_scancache_reset_modify (thread_p, *scan_cache, hfid, class_oid);
      if (r != NO_ERROR)
        {
          return r;
        }
    }
    }

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_scancache_start_internal () - Start caching information for a heap scan
 *   return: NO_ERROR
 *   scan_cache(in/out): Scan cache
 *   hfid(in): Heap file identifier of the scan cache or NULL
 *             If NULL is given heap_get is the only function that can
 *             be used with the scan cache.
 *   class_oid(in): Class identifier of scan cache
 *                  For any class, NULL or NULL_OID can be given
 *   cache_last_fix_page(in): Wheater or not to cache the last fetched page
 *                            between scan objects ?
 *   is_queryscan(in):
 *   is_indexscan(in):
 *
 */
static int
heap_scancache_start_internal (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, const HFID * hfid,
                   const OID * class_oid, int cache_last_fix_page, bool is_queryscan, int is_indexscan,
                   MVCC_SNAPSHOT * mvcc_snapshot)
{
  int ret = NO_ERROR;

  if (class_oid != NULL)
    {
      /* 
       * Scanning the instances of a specific class
       */
      scan_cache->node.class_oid = *class_oid;

      if (is_queryscan == true)
    {
      /* 
       * Acquire a lock for the heap scan so that the class is not updated
       * during the scan of the heap. This can happen in transaction isolation
       * levels that release the locks of the class when the class is read.
       */
      if (lock_scan (thread_p, class_oid, LK_UNCOND_LOCK, IS_LOCK) != LK_GRANTED)
        {
          goto exit_on_error;
        }
    }

      ret =
    heap_get_hfid_and_file_type_from_class_oid (thread_p, class_oid, &scan_cache->node.hfid,
                            &scan_cache->file_type);
      if (ret != NO_ERROR)
    {
      ASSERT_ERROR ();
      return ret;
    }
      assert (hfid == NULL || HFID_EQ (hfid, &scan_cache->node.hfid));
      assert (scan_cache->file_type == FILE_HEAP || scan_cache->file_type == FILE_HEAP_REUSE_SLOTS);
    }
  else
    {
      /* 
       * Scanning the instances of any class in the heap
       */
      OID_SET_NULL (&scan_cache->node.class_oid);

      if (hfid == NULL)
    {
      HFID_SET_NULL (&scan_cache->node.hfid);
      scan_cache->node.hfid.vfid.volid = NULL_VOLID;
      scan_cache->file_type = FILE_UNKNOWN_TYPE;
    }
      else
    {
      scan_cache->node.hfid.vfid.volid = hfid->vfid.volid;
      scan_cache->node.hfid.vfid.fileid = hfid->vfid.fileid;
      scan_cache->node.hfid.hpgid = hfid->hpgid;
      if (file_get_type (thread_p, &hfid->vfid, &scan_cache->file_type) != NO_ERROR)
        {
          ASSERT_ERROR ();
          goto exit_on_error;
        }
      if (scan_cache->file_type == FILE_UNKNOWN_TYPE)
        {
          assert_release (false);
          goto exit_on_error;
        }
    }
    }

  scan_cache->page_latch = S_LOCK;

  scan_cache->cache_last_fix_page = cache_last_fix_page;
  PGBUF_INIT_WATCHER (&(scan_cache->page_watcher), PGBUF_ORDERED_HEAP_NORMAL, hfid);
  scan_cache->area = NULL;
  scan_cache->area_size = -1;
  scan_cache->num_btids = 0;
  scan_cache->index_stat_info = NULL;

  scan_cache->debug_initpattern = HEAP_DEBUG_SCANCACHE_INITPATTERN;
  scan_cache->mvcc_snapshot = mvcc_snapshot;
  scan_cache->partition_list = NULL;

  return ret;

exit_on_error:

  HFID_SET_NULL (&scan_cache->node.hfid);
  scan_cache->node.hfid.vfid.volid = NULL_VOLID;
  OID_SET_NULL (&scan_cache->node.class_oid);
  scan_cache->page_latch = NULL_LOCK;
  scan_cache->cache_last_fix_page = false;
  PGBUF_INIT_WATCHER (&(scan_cache->page_watcher), PGBUF_ORDERED_RANK_UNDEFINED, PGBUF_ORDERED_NULL_HFID);
  scan_cache->area = NULL;
  scan_cache->area_size = 0;
  scan_cache->num_btids = 0;
  scan_cache->index_stat_info = NULL;
  scan_cache->file_type = FILE_UNKNOWN_TYPE;
  scan_cache->debug_initpattern = 0;
  scan_cache->mvcc_snapshot = NULL;
  scan_cache->partition_list = NULL;

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_scancache_start () - Start caching information for a heap scan
 *   return: NO_ERROR
 *   scan_cache(in/out): Scan cache
 *   hfid(in): Heap file identifier of the scan cache or NULL
 *             If NULL is given heap_get is the only function that can
 *             be used with the scan cache.
 *   class_oid(in): Class identifier of scan cache
 *                  For any class, NULL or NULL_OID can be given
 *   cache_last_fix_page(in): Wheater or not to cache the last fetched page
 *                            between scan objects ?
 *   is_indexscan(in):
 *
 */
int
heap_scancache_start (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, const HFID * hfid, const OID * class_oid,
              int cache_last_fix_page, int is_indexscan, MVCC_SNAPSHOT * mvcc_snapshot)
{
  return heap_scancache_start_internal (thread_p, scan_cache, hfid, class_oid, cache_last_fix_page, true, is_indexscan,
                    mvcc_snapshot);
}

/*
 * heap_scancache_start_modify () - Start caching information for heap
 *                                modifications
 *   return: NO_ERROR
 *   scan_cache(in/out): Scan cache
 *   hfid(in): Heap file identifier of the scan cache or NULL
 *             If NULL is given heap_get is the only function that can
 *             be used with the scan cache.
 *   class_oid(in): Class identifier of scan cache
 *                  For any class, NULL or NULL_OID can be given
 *   op_type(in):
 *
 * Note: A scancache structure is started for heap modifications.
 * The scan_cache structure is used to modify objects of the heap
 * with heap_insert, heap_update, and heap_delete. The scan structure
 * is used to cache information about the latest used page which
 * can be used by the following function to guess where to insert
 * objects, or other updates and deletes on the same page.
 * Good when we are updating things in a sequential way.
 *
 * The heap manager automatically resets the scan_cache structure
 * when it is used with a different heap. That is, the scan_cache
 * is reset with the heap and class of the insertion, update, and
 * delete. Therefore, you could pass NULLs to hfid, and class_oid
 * to this function, but that it is not recommended.
 */
int
heap_scancache_start_modify (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, const HFID * hfid,
                 const OID * class_oid, int op_type, MVCC_SNAPSHOT * mvcc_snapshot)
{
  OR_CLASSREP *classrepr = NULL;
  int classrepr_cacheindex = -1;
  int malloc_size, i;
  int ret = NO_ERROR;

  if (heap_scancache_start_internal (thread_p, scan_cache, hfid, NULL, false, false, false, mvcc_snapshot) != NO_ERROR)
    {
      goto exit_on_error;
    }

  if (class_oid != NULL)
    {
      ret = heap_scancache_reset_modify (thread_p, scan_cache, hfid, class_oid);
      if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }
    }
  else
    {
      scan_cache->page_latch = X_LOCK;
    }

  if (BTREE_IS_MULTI_ROW_OP (op_type) && class_oid != NULL && !OID_EQ (class_oid, oid_Root_class_oid))
    {
      /* get class representation to find the total number of indexes */
      classrepr = heap_classrepr_get (thread_p, (OID *) class_oid, NULL, NULL_REPRID, &classrepr_cacheindex);
      if (classrepr == NULL)
    {
      goto exit_on_error;
    }
      scan_cache->num_btids = classrepr->n_indexes;

      if (scan_cache->num_btids > 0)
    {
      /* allocate local btree statistical information structure */
      malloc_size = sizeof (BTREE_UNIQUE_STATS) * scan_cache->num_btids;

      if (scan_cache->index_stat_info != NULL)
        {
          db_private_free (thread_p, scan_cache->index_stat_info);
        }

      scan_cache->index_stat_info = (BTREE_UNIQUE_STATS *) db_private_alloc (thread_p, malloc_size);
      if (scan_cache->index_stat_info == NULL)
        {
          ret = ER_OUT_OF_VIRTUAL_MEMORY;
          heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);
          goto exit_on_error;
        }
      /* initialize the structure */
      for (i = 0; i < scan_cache->num_btids; i++)
        {
          BTID_COPY (&(scan_cache->index_stat_info[i].btid), &(classrepr->indexes[i].btid));
          scan_cache->index_stat_info[i].num_nulls = 0;
          scan_cache->index_stat_info[i].num_keys = 0;
          scan_cache->index_stat_info[i].num_oids = 0;
        }
    }

      /* free class representation */
      heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);
    }

  /* In case of SINGLE_ROW_INSERT, SINGLE_ROW_UPDATE, SINGLE_ROW_DELETE, or SINGLE_ROW_MODIFY, the 'num_btids' and
   * 'index_stat_info' of scan cache structure have to be set as 0 and NULL, respectively. */

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_scancache_force_modify () -
 *   return: NO_ERROR
 *   scan_cache(in):
 */
static int
heap_scancache_force_modify (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache)
{
  if (scan_cache == NULL || scan_cache->debug_initpattern != HEAP_DEBUG_SCANCACHE_INITPATTERN)
    {
      return NO_ERROR;
    }

  /* Free fetched page */
  if (scan_cache->page_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &(scan_cache->page_watcher));
    }

  return NO_ERROR;
}

/*
 * heap_scancache_reset_modify () - Reset the current caching information
 *   return: NO_ERROR
 *   scan_cache(in/out): Scan cache
 *   hfid(in): Heap file identifier of the scan cache
 *   class_oid(in): Class identifier of scan cache
 *
 * Note: Any page that has been cached under the current scan cache is
 * freed and the scancache structure is reinitialized with the
 * new information.
 */
static int
heap_scancache_reset_modify (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, const HFID * hfid,
                 const OID * class_oid)
{
  int ret;

  ret = heap_scancache_force_modify (thread_p, scan_cache);
  if (ret != NO_ERROR)
    {
      return ret;
    }

  if (class_oid != NULL)
    {
      if (!OID_EQ (class_oid, &scan_cache->node.class_oid))
    {
      ret =
        heap_get_hfid_and_file_type_from_class_oid (thread_p, class_oid, &scan_cache->node.hfid,
                            &scan_cache->file_type);
      if (ret != NO_ERROR)
        {
          ASSERT_ERROR ();
          return ret;
        }
      assert (HFID_EQ (&scan_cache->node.hfid, hfid));
      scan_cache->node.class_oid = *class_oid;
    }
    }
  else
    {
      OID_SET_NULL (&scan_cache->node.class_oid);

      if (!HFID_EQ (&scan_cache->node.hfid, hfid))
    {
      scan_cache->node.hfid.vfid.volid = hfid->vfid.volid;
      scan_cache->node.hfid.vfid.fileid = hfid->vfid.fileid;
      scan_cache->node.hfid.hpgid = hfid->hpgid;

      ret = file_get_type (thread_p, &hfid->vfid, &scan_cache->file_type);
      if (ret != NO_ERROR)
        {
          ASSERT_ERROR ();
          return ret;
        }
      if (scan_cache->file_type == FILE_UNKNOWN_TYPE)
        {
          assert_release (false);
          return ER_FAILED;
        }
    }
    }
  scan_cache->page_latch = X_LOCK;

  return ret;
}

/*
 * heap_scancache_quick_start () - Start caching information for a heap scan
 *   return: NO_ERROR
 *   scan_cache(in/out): Scan cache
 *
 * Note: This is a quick way to initialize a scancahe structure. It
 * should be used only when we would like to peek only one object
 * (heap_get). This function will cache the last fetched page by default.
 *
 *  This function was created to avoid some of the overhead
 *  associated with scancahe(e.g., find best pages, lock the heap)
 *  since we are not really scanning the heap.
 *
 *  For other needs/uses, please refer to heap_scancache_start ().
 *
 * Note: Using many scancaches with the cached_fix page option at the
 * same time should be avoided since page buffers are fixed and
 * locked for future references and there is a limit of buffers
 * in the page buffer pool. This is analogous to fetching many
 * pages at the same time. The page buffer pool is expanded when
 * needed, however, developers must pay special attention to
 * avoid this situation.
 */
int
heap_scancache_quick_start (HEAP_SCANCACHE * scan_cache)
{
  heap_scancache_quick_start_internal (scan_cache, NULL);

  scan_cache->page_latch = S_LOCK;

  return NO_ERROR;
}

/*
 * heap_scancache_quick_start_modify () - Start caching information
 *                                      for a heap modifications
 *   return: NO_ERROR
 *   scan_cache(in/out): Scan cache
 */
int
heap_scancache_quick_start_modify (HEAP_SCANCACHE * scan_cache)
{
  heap_scancache_quick_start_internal (scan_cache, NULL);

  scan_cache->page_latch = X_LOCK;

  return NO_ERROR;
}

/*
 * heap_scancache_quick_start_internal () -
 *
 *   return: NO_ERROR
 *   scan_cache(in/out): Scan cache
 */
static int
heap_scancache_quick_start_internal (HEAP_SCANCACHE * scan_cache, const HFID * hfid)
{
  HFID_SET_NULL (&scan_cache->node.hfid);
  if (hfid == NULL)
    {
      scan_cache->node.hfid.vfid.volid = NULL_VOLID;
      PGBUF_INIT_WATCHER (&(scan_cache->page_watcher), PGBUF_ORDERED_HEAP_NORMAL, PGBUF_ORDERED_NULL_HFID);
    }
  else
    {
      HFID_COPY (&scan_cache->node.hfid, hfid);
      PGBUF_INIT_WATCHER (&(scan_cache->page_watcher), PGBUF_ORDERED_HEAP_NORMAL, hfid);
    }
  OID_SET_NULL (&scan_cache->node.class_oid);
  scan_cache->page_latch = S_LOCK;
  scan_cache->cache_last_fix_page = true;
  scan_cache->area = NULL;
  scan_cache->area_size = 0;
  scan_cache->num_btids = 0;
  scan_cache->index_stat_info = NULL;
  scan_cache->file_type = FILE_UNKNOWN_TYPE;
  scan_cache->debug_initpattern = HEAP_DEBUG_SCANCACHE_INITPATTERN;
  scan_cache->mvcc_snapshot = NULL;
  scan_cache->partition_list = NULL;

  return NO_ERROR;
}

/*
 * heap_scancache_quick_end () - Stop caching information for a heap scan
 *   return: NO_ERROR
 *   scan_cache(in/out): Scan cache
 *
 * Note: Any fixed heap page on the given scan is freed and any memory
 * allocated by this scan is also freed. The scan_cache structure
 * is undefined.  This function does not update any space statistics.
 */
static int
heap_scancache_quick_end (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache)
{
  int ret = NO_ERROR;

  if (scan_cache->debug_initpattern != HEAP_DEBUG_SCANCACHE_INITPATTERN)
    {
      er_log_debug (ARG_FILE_LINE, "heap_scancache_quick_end: Your scancache is not initialized");
      ret = ER_GENERIC_ERROR;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 0);
    }
  else
    {
      if (scan_cache->index_stat_info != NULL)
    {
      /* deallocate memory space allocated for index stat info. */
      db_private_free_and_init (thread_p, scan_cache->index_stat_info);
      scan_cache->num_btids = 0;
    }

      if (scan_cache->cache_last_fix_page == true)
    {
      /* Free fetched page */
      if (scan_cache->page_watcher.pgptr != NULL)
        {
          pgbuf_ordered_unfix (thread_p, &scan_cache->page_watcher);
        }
    }

      /* Free memory */
      if (scan_cache->area)
    {
      db_private_free_and_init (thread_p, scan_cache->area);
    }

      if (scan_cache->partition_list)
    {
      HEAP_SCANCACHE_NODE_LIST *next_node = NULL;
      HEAP_SCANCACHE_NODE_LIST *curr_node = NULL;

      curr_node = scan_cache->partition_list;

      while (curr_node != NULL)
        {
          next_node = curr_node->next;
          db_private_free_and_init (thread_p, curr_node);
          curr_node = next_node;
        }
    }
    }

  HFID_SET_NULL (&scan_cache->node.hfid);
  scan_cache->node.hfid.vfid.volid = NULL_VOLID;
  OID_SET_NULL (&scan_cache->node.class_oid);
  scan_cache->page_latch = NULL_LOCK;
  assert (PGBUF_IS_CLEAN_WATCHER (&(scan_cache->page_watcher)));
  scan_cache->area = NULL;
  scan_cache->area_size = 0;
  scan_cache->file_type = FILE_UNKNOWN_TYPE;
  scan_cache->debug_initpattern = 0;

  return ret;
}

/*
 * heap_scancache_end_internal () -
 *   return: NO_ERROR
 *   scan_cache(in):
 *   scan_state(in):
 */
static int
heap_scancache_end_internal (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, bool scan_state)
{
  int ret = NO_ERROR;

  if (scan_cache->debug_initpattern != HEAP_DEBUG_SCANCACHE_INITPATTERN)
    {
      er_log_debug (ARG_FILE_LINE, "heap_scancache_end_internal: Your scancache is not initialized");
      return ER_FAILED;
    }

  ret = heap_scancache_quick_end (thread_p, scan_cache);

  return ret;
}

/*
 * heap_scancache_end () - Stop caching information for a heap scan
 *   return: NO_ERROR
 *   scan_cache(in/out): Scan cache
 *
 * Note: Any fixed heap page on the given scan is freed and any memory
 * allocated by this scan is also freed. The scan_cache structure is undefined.
 */
int
heap_scancache_end (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache)
{
  int ret;

  ret = heap_scancache_end_internal (thread_p, scan_cache, END_SCAN);

  return NO_ERROR;
}

/*
 * heap_scancache_end_when_scan_will_resume () -
 *   return:
 *   scan_cache(in):
 */
int
heap_scancache_end_when_scan_will_resume (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache)
{
  int ret;

  ret = heap_scancache_end_internal (thread_p, scan_cache, CONTINUE_SCAN);

  return NO_ERROR;
}

/*
 * heap_scancache_end_modify () - End caching information for a heap
 *                modification cache
 *   return:
 *   scan_cache(in/out): Scan cache
 *
 * Note: Any fixed heap page on the given scan is freed. The heap
 * best find space statistics for the heap are completely updated
 * with the ones stored in the scan cache.
 */
void
heap_scancache_end_modify (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache)
{
  int ret;

  ret = heap_scancache_force_modify (thread_p, scan_cache);
  if (ret == NO_ERROR)
    {
      ret = heap_scancache_quick_end (thread_p, scan_cache);
    }
}

/*
 * heap_get_if_diff_chn () - Get specified object of the given slotted page when
 *                       its cache coherency number is different
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS,
 *                      S_SUCCESS_CHN_UPTODATE,
 *                      S_DOESNT_FIT,
 *                      S_DOESNT_EXIST)
 *   pgptr(in): Pointer to slotted page
 *   slotid(in): Slot identifier of current record.
 *   recdes(in/out): Pointer to a record descriptor. Will be modified to
 *                   describe the desired record.
 *   ispeeking(in): Indicates whether the record is going to be copied
 *                  (like a copy) or peeked (read at the buffer).
 *   chn(in): Cache coherency number or NULL_CHN
 *
 * Note: If the given CHN is the same as the chn of the specified
 * object in the slotted page, the object may not be placed in
 * the given record descriptor. If the given CHN is NULL_CHN or
 * is not given, then the following process is followed depending
 * upon if we are peeking or not:
 * When ispeeking is PEEK, the desired record is peeked onto the
 * buffer pool. The address of the record descriptor is set
 * to the portion of the buffer pool where the record is stored.
 * For more information on peeking description, see the slotted module.
 *
 * When ispeeking is COPY, the desired record is read
 * onto the area pointed by the record descriptor. If the record
 * does not fit in such an area, the length of the record is
 * returned as a negative value in recdes->length and an error
 * condition is indicated.
 */
static SCAN_CODE
heap_get_if_diff_chn (THREAD_ENTRY * thread_p, PAGE_PTR pgptr, INT16 slotid, RECDES * recdes, bool ispeeking, int chn,
              MVCC_SNAPSHOT * mvcc_snapshot)
{
  RECDES chn_recdes;        /* Used when we need to compare the cache coherency number and we are not peeking */
  SCAN_CODE scan;
  MVCC_REC_HEADER mvcc_header;

  /* 
   * Don't retrieve the object when the object has the same cache
   * coherency number given by the caller. That is, the caller has the
   * valid cached object.
   */

  if (ispeeking == PEEK)
    {
      scan = spage_get_record (thread_p, pgptr, slotid, recdes, PEEK);
      if (scan != S_SUCCESS)
    {
      return scan;
    }

      /* For MVCC we need to obtain header and verify header */
      or_mvcc_get_header (recdes, &mvcc_header);
      if (scan == S_SUCCESS && mvcc_snapshot != NULL && mvcc_snapshot->snapshot_fnc != NULL)
    {
      if (mvcc_snapshot->snapshot_fnc (thread_p, &mvcc_header, mvcc_snapshot) == TOO_OLD_FOR_SNAPSHOT)
        {
          /* consider snapshot is not satisified only in case of TOO_OLD_FOR_SNAPSHOT;
           * TOO_NEW_FOR_SNAPSHOT records should be accepted, e.g. a recently updated record, locked at select */
          return S_SNAPSHOT_NOT_SATISFIED;
        }
    }
      if (MVCC_IS_CHN_UPTODATE (&mvcc_header, chn))
    {
      /* Test chn if MVCC is disabled for record or if delete MVCCID is invalid and the record is inserted by
       * current transaction. */
      /* When testing chn is not required, the result is considered up-to-date. */
      scan = S_SUCCESS_CHN_UPTODATE;
    }
    }
  else
    {
      scan = spage_get_record (thread_p, pgptr, slotid, &chn_recdes, PEEK);
      if (scan != S_SUCCESS)
    {
      return scan;
    }

      /* For MVCC we need to obtain header and verify header */
      or_mvcc_get_header (&chn_recdes, &mvcc_header);
      if (scan == S_SUCCESS && mvcc_snapshot != NULL && mvcc_snapshot->snapshot_fnc != NULL)
    {
      if (mvcc_snapshot->snapshot_fnc (thread_p, &mvcc_header, mvcc_snapshot) == TOO_OLD_FOR_SNAPSHOT)
        {
          /* consider snapshot is not satisified only in case of TOO_OLD_FOR_SNAPSHOT;
           * TOO_NEW_FOR_SNAPSHOT records should be accepted, e.g. a recently updated record, locked at select */
          return S_SNAPSHOT_NOT_SATISFIED;
        }
    }
      if (MVCC_IS_CHN_UPTODATE (&mvcc_header, chn))
    {
      /* Test chn if MVCC is disabled for record or if delete MVCCID is invalid and the record is inserted by
       * current transaction. */
      /* When testing chn is not required, the result is considered up-to-date. */
      scan = S_SUCCESS_CHN_UPTODATE;
    }

      if (scan != S_SUCCESS_CHN_UPTODATE)
    {
      /* 
       * Note that we could copy the recdes.data from chn_recdes.data, but
       * I don't think it is much difference here, and we will have to deal
       * with all not fit conditions and so on, so we decide to use
       * spage_get_record instead.
       */
      scan = spage_get_record (thread_p, pgptr, slotid, recdes, COPY);
    }
    }

  return scan;
}

/*
 * heap_prepare_get_context () - Prepare for obtaining/processing heap object.
 *              It may get class_oid, record_type, home page
 *              and also forward_oid and forward_page in some
 *              cases.
 *
 * return        : SCAN_CODE: S_ERROR, S_DOESNT_EXIST and S_SUCCESS.
 * thread_p (in)     : Thread entry.
 * context (in/out)      : Heap get context used to store the information required for heap objects processing.
 * is_heap_scan (in)     : Used to decide if it is acceptable to reach deleted objects or not.
 * non_ex_handling_type (in): Handling type for deleted objects
 *                - LOG_ERROR_IF_DELETED: write the 
 *              ER_HEAP_UNKNOWN_OBJECT error to log
 *                            - LOG_WARNING_IF_DELETED: set only warning
 *
 *  Note : the caller should manage the page unfix of both home and forward
 *     pages (even in case of error, there may be pages latched).
 *     The functions uses a multiple page latch; in some extreme cases,
 *     if the home page was unfixed during fwd page fix, we need to recheck
 *     the home page OID is still valid and re-PEEK the home record. We
 *     allow this to repeat once.
 *     For performance:
 *     Make sure page unfix is performed in order fwd page, then home page.
 *     Normal fix sequence (first attempt) is home page, then fwd page; if
 *     the fwd page is unfixed before home, another thread will attempt to
 *     fix fwd page, after having home fix; first try (CONDITIONAL) will
 *     fail, and will trigger an ordered fix + UNCONDITIONAL.
 */
SCAN_CODE
heap_prepare_get_context (THREAD_ENTRY * thread_p, HEAP_GET_CONTEXT * context, bool is_heap_scan,
              NON_EXISTENT_HANDLING non_ex_handling_type)
{
  SPAGE_SLOT *slot_p = NULL;
  RECDES peek_recdes;
  SCAN_CODE scan = S_SUCCESS;
  int try_count = 0;
  int try_max = 1;
  int ret;
#if defined (SA_MODE)
  bool is_system_class = false;
#endif /* SA_MODE */

  assert (context->oid_p != NULL);

try_again:

  /* First make sure object home_page is fixed. */
  ret = heap_prepare_object_page (thread_p, context->oid_p, &context->home_page_watcher, context->latch_mode);
  if (ret != NO_ERROR)
    {
      if (ret == ER_HEAP_UNKNOWN_OBJECT)
    {
      /* bad page id, consider the object does not exist and let the caller handle the case */
      return S_DOESNT_EXIST;
    }

      goto error;
    }

  /* Output class_oid if necessary. */
  if (context->class_oid_p != NULL && OID_ISNULL (context->class_oid_p)
      && heap_get_class_oid_from_page (thread_p, context->home_page_watcher.pgptr, context->class_oid_p) != NO_ERROR)
    {
      /* Unexpected. */
      assert_release (false);
      goto error;
    }

  /* Get slot. */
  slot_p = spage_get_slot (context->home_page_watcher.pgptr, context->oid_p->slotid);
  if (slot_p == NULL)
    {
      /* Slot doesn't exist. */
      if (!is_heap_scan)
    {
      /* Do not set error for heap scan and get record info. */
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, context->oid_p->volid,
          context->oid_p->pageid, context->oid_p->slotid);
    }

      /* Output record type as REC_UNKNOWN. */
      context->record_type = REC_UNKNOWN;

      return S_DOESNT_EXIST;
    }

  /* Output record type. */
  context->record_type = slot_p->record_type;

  if (context->fwd_page_watcher.pgptr != NULL && slot_p->record_type != REC_RELOCATION
      && slot_p->record_type != REC_BIGONE)
    {
      /* Forward page no longer required. */
      pgbuf_ordered_unfix (thread_p, &context->fwd_page_watcher);
    }

  /* Fix required pages. */
  switch (slot_p->record_type)
    {
    case REC_RELOCATION:
      /* Need to get forward_oid and fix forward page */
      scan = spage_get_record (thread_p, context->home_page_watcher.pgptr, context->oid_p->slotid, &peek_recdes, PEEK);
      if (scan != S_SUCCESS)
    {
      /* Unexpected. */
      assert_release (false);
      goto error;
    }
      /* Output forward_oid. */
      COPY_OID (&context->forward_oid, (OID *) peek_recdes.data);

      /* Try to latch forward_page. */
      PGBUF_WATCHER_COPY_GROUP (&context->fwd_page_watcher, &context->home_page_watcher);
      ret = heap_prepare_object_page (thread_p, &context->forward_oid, &context->fwd_page_watcher, context->latch_mode);
      if (ret == NO_ERROR)
    {
      /* Pages successfully fixed. */
      if (context->home_page_watcher.page_was_unfixed)
        {
          /* Home_page/forward_page are both fixed. However, since home page was unfixed, record may have changed
           * (record type has changed or just the relocation link). Go back and repeat steps (if nothing was
           * changed, pages are already fixed). */
          if (try_count++ < try_max)
        {
          context->home_page_watcher.page_was_unfixed = false;
          goto try_again;
        }
          else
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PAGE_LATCH_ABORTED, 2, context->forward_oid.volid,
              context->forward_oid.pageid);
        }

          goto error;
        }
      return S_SUCCESS;
    }

      goto error;

    case REC_BIGONE:
      /* Need to get forward_oid and forward_page (first overflow page). */
      scan = spage_get_record (thread_p, context->home_page_watcher.pgptr, context->oid_p->slotid, &peek_recdes, PEEK);
      if (scan != S_SUCCESS)
    {
      /* Unexpected. */
      assert_release (false);
      goto error;
    }
      /* Output forward_oid. */
      COPY_OID (&context->forward_oid, (OID *) peek_recdes.data);

      /* Fix overflow page. Since overflow pages should be always accessed with their home pages latched, unconditional 
       * latch should work; However, we need to use the same ordered_fix approach. */
      PGBUF_WATCHER_RESET_RANK (&context->fwd_page_watcher, PGBUF_ORDERED_HEAP_OVERFLOW);
      PGBUF_WATCHER_COPY_GROUP (&context->fwd_page_watcher, &context->home_page_watcher);
      ret = heap_prepare_object_page (thread_p, &context->forward_oid, &context->fwd_page_watcher, context->latch_mode);
      if (ret == NO_ERROR)
    {
      /* Pages successfully fixed. */
      if (context->home_page_watcher.page_was_unfixed)
        {
          /* This is not expected. */
          assert (false);
          goto error;
        }
      return S_SUCCESS;
    }

      goto error;

    case REC_ASSIGN_ADDRESS:
      /* Object without content.. only the address has been assigned */
      if (is_heap_scan)
    {
      /* Just ignore record. */
      return S_DOESNT_EXIST;
    }
      if (spage_check_slot_owner (thread_p, context->home_page_watcher.pgptr, context->oid_p->slotid))
    {
      er_set (ER_WARNING_SEVERITY, ARG_FILE_LINE, ER_HEAP_NODATA_NEWADDRESS, 3, context->oid_p->volid,
          context->oid_p->pageid, context->oid_p->slotid);
      return S_DOESNT_EXIST;
    }
      else
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, context->oid_p->volid,
          context->oid_p->pageid, context->oid_p->slotid);
      goto error;
    }

    case REC_HOME:
      /* Only home page is needed. */
      return S_SUCCESS;

    case REC_DELETED_WILL_REUSE:
    case REC_MARKDELETED:
      /* Vacuumed/deleted record. */
      if (is_heap_scan)
    {
      /* Just ignore record. */
      return S_DOESNT_EXIST;
    }
#if defined(SA_MODE)
      /* Accessing a REC_MARKDELETED record from a system class can happen in SA mode, when no MVCC operations have
       * been performed on the system class. */
      if (oid_is_system_class (context->class_oid_p, &is_system_class) != NO_ERROR)
    {
      goto error;
    }
      if (is_system_class == true)
    {
      er_set (ER_WARNING_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, context->oid_p->volid,
          context->oid_p->pageid, context->oid_p->slotid);
      return S_DOESNT_EXIST;
    }
#endif /* SA_MODE */

      if (OID_EQ (context->class_oid_p, oid_Root_class_oid) || OID_EQ (context->class_oid_p, oid_User_class_oid)
      || non_ex_handling_type == LOG_WARNING_IF_DELETED)
    {
      /* A deleted class record, corresponding to a deleted class can be accessed through catalog update operations 
       * on another class. This is possible if a class has an attribute holding a domain that references the
       * dropped class. Another situation is the client request for authentication, which fetches the object (an
       * instance of db_user) using dirty version. If it has been removed, it will be found as a deleted record. */
      er_set (ER_WARNING_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, context->oid_p->volid,
          context->oid_p->pageid, context->oid_p->slotid);
    }
      else
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, context->oid_p->volid,
          context->oid_p->pageid, context->oid_p->slotid);
    }
      return S_DOESNT_EXIST;

    case REC_NEWHOME:
      if (is_heap_scan)
    {
      /* Just ignore record. */
      return S_DOESNT_EXIST;
    }
      /* REC_NEWHOME are only allowed to be accessed through REC_RELOCATION slots. */
      /* Fall through to error. */
    default:
      /* Unexpected case. */
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_BAD_OBJECT_TYPE, 3, context->oid_p->volid,
          context->oid_p->pageid, context->oid_p->slotid);
      goto error;
    }

  /* Impossible */
  assert_release (false);
error:
  assert (ret == ER_LK_PAGE_TIMEOUT || er_errid () != NO_ERROR);

  heap_clean_get_context (thread_p, context);
  return S_ERROR;
}

/*
 * heap_get_mvcc_header () - Get record MVCC header.
 *
 * return        : SCAN_CODE: S_SUCCESS, S_ERROR or S_DOESNT_EXIST.
 * thread_p (in)     : Thread entry.
 * context (in)      : Heap get context.
 * mvcc_header (out) : Record MVCC header.
 *
 * NOTE: This function gets MVCC header, if it has everything needed already
 *   obtained: pages latched, forward OID (if the case), record type.
 */
SCAN_CODE
heap_get_mvcc_header (THREAD_ENTRY * thread_p, HEAP_GET_CONTEXT * context, MVCC_REC_HEADER * mvcc_header)
{
  RECDES peek_recdes;
  SCAN_CODE scan_code;
  PAGE_PTR home_page, forward_page;
  const OID *oid;

  assert (context != NULL && context->oid_p != NULL);

  oid = context->oid_p;
  home_page = context->home_page_watcher.pgptr;
  forward_page = context->fwd_page_watcher.pgptr;

  assert (home_page != NULL);
  assert (pgbuf_get_page_id (home_page) == oid->pageid && pgbuf_get_volume_id (home_page) == oid->volid);
  assert (context->record_type == REC_HOME || context->record_type == REC_RELOCATION
      || context->record_type == REC_BIGONE);
  assert (context->record_type == REC_HOME
      || (forward_page != NULL && pgbuf_get_page_id (forward_page) == context->forward_oid.pageid
          && pgbuf_get_volume_id (forward_page) == context->forward_oid.volid));
  assert (mvcc_header != NULL);

  /* Get header and verify snapshot. */
  switch (context->record_type)
    {
    case REC_HOME:
      scan_code = spage_get_record (thread_p, home_page, oid->slotid, &peek_recdes, PEEK);
      if (scan_code != S_SUCCESS)
    {
      /* Unexpected. */
      assert (false);
      return S_ERROR;
    }
      if (or_mvcc_get_header (&peek_recdes, mvcc_header) != NO_ERROR)
    {
      /* Unexpected. */
      assert (false);
      return S_ERROR;
    }
      return S_SUCCESS;
    case REC_BIGONE:
      assert (forward_page != NULL);
      if (heap_get_mvcc_rec_header_from_overflow (forward_page, mvcc_header, &peek_recdes) != NO_ERROR)
    {
      /* Unexpected. */
      assert (false);
      return S_ERROR;
    }
      return S_SUCCESS;
    case REC_RELOCATION:
      assert (forward_page != NULL);
      scan_code = spage_get_record (thread_p, forward_page, context->forward_oid.slotid, &peek_recdes, PEEK);
      if (scan_code != S_SUCCESS)
    {
      /* Unexpected. */
      assert (false);
      return S_ERROR;
    }
      if (or_mvcc_get_header (&peek_recdes, mvcc_header) != NO_ERROR)
    {
      /* Unexpected. */
      assert (false);
      return S_ERROR;
    }
      return S_SUCCESS;
    default:
      /* Unexpected. */
      assert (false);
      return S_ERROR;
    }

  /* Impossible. */
  assert (false);
  return S_ERROR;
}

/*
 * heap_get_record_data_when_all_ready () - Get record data when all required information is known. This can work only
 *                                          for record types that actually have data: REC_HOME, REC_RELOCATION and
 *                                          REC_BIGONE. Required information: home_page, forward_oid and forward page
 *                                          for REC_RELOCATION and REC_BIGONE, and record type.
 *
 * return         : SCAN_CODE: S_SUCCESS, S_ERROR, S_DOESNT_FIT.
 * thread_p (in)      : Thread entry.
 * context (in/out)   : Heap get context. Should contain all required information for object retrieving
 */
SCAN_CODE
heap_get_record_data_when_all_ready (THREAD_ENTRY * thread_p, HEAP_GET_CONTEXT * context)
{
  HEAP_SCANCACHE *scan_cache_p = context->scan_cache;

  /* We have everything set up to get record data. */
  assert (context != NULL);

  /* Assert ispeeking, scan_cache and recdes are compatible. If ispeeking is PEEK, it is the caller responsabilty to
   * keep the page latched while the recdes don't go out of scope. If ispeeking is COPY, we must have a preallocated
   * area to copy to. This means either scan_cache is not NULL (and scan_cache->area can be used) or recdes->data is 
   * not NULL (and recdes->area_size defines how much can be copied). */
  assert ((context->ispeeking == PEEK)
      || (context->ispeeking == COPY && (scan_cache_p != NULL || context->recdes_p->data != NULL)));

  switch (context->record_type)
    {
    case REC_RELOCATION:
      /* Don't peek REC_RELOCATION. */
      if (scan_cache_p != NULL && (context->ispeeking != 0 || context->recdes_p->data == NULL)
      && heap_scan_cache_allocate_recdes_data (thread_p, scan_cache_p, context->recdes_p,
                           DB_PAGESIZE * 2) != NO_ERROR)
    {
      ASSERT_ERROR ();
      return S_ERROR;
    }

      return spage_get_record (thread_p, context->fwd_page_watcher.pgptr, context->forward_oid.slotid,
                   context->recdes_p, COPY);
    case REC_BIGONE:
      return heap_get_bigone_content (thread_p, scan_cache_p, context->ispeeking, &context->forward_oid,
                      context->recdes_p);
    case REC_HOME:
      if (scan_cache_p != NULL && context->ispeeking == COPY && context->recdes_p->data == NULL
      && heap_scan_cache_allocate_recdes_data (thread_p, scan_cache_p, context->recdes_p,
                           DB_PAGESIZE * 2) != NO_ERROR)
    {
      ASSERT_ERROR ();
      return S_ERROR;
    }
      return spage_get_record (thread_p, context->home_page_watcher.pgptr, context->oid_p->slotid, context->recdes_p,
                   context->ispeeking);
    default:
      break;
    }
  /* Shouldn't be here. */
  return S_ERROR;
}

/*
 * heap_next_internal () - Retrieve of peek next object.
 *
 * return            : SCAN_CODE (Either of S_SUCCESS, S_DOESNT_FIT,
 *                 S_END, S_ERROR).
 * thread_p (in)         : Thread entry.
 * hfid (in)             : Heap file identifier.
 * class_oid (in)        : Class object identifier.
 * next_oid (in/out)         : Object identifier of current record. Will be
 *                 set to next available record or NULL_OID
 *                 when there is not one.
 * recdes (in)           : Pointer to a record descriptor. Will be
 *                 modified to describe the new record.
 * scan_cache (in)       : Scan cache or NULL
 * ispeeking (in)        : PEEK when the object is peeked scan_cache can't
 *                 be NULL COPY when the object is copied.
 * cache_recordinfo (in/out) : DB_VALUE pointer array that caches record
 *                 information values.
 */
static SCAN_CODE
heap_next_internal (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, OID * next_oid, RECDES * recdes,
            HEAP_SCANCACHE * scan_cache, bool ispeeking, bool reversed_direction, DB_VALUE ** cache_recordinfo)
{
  VPID vpid;
  VPID *vpidptr_incache;
  INT16 type = REC_UNKNOWN;
  OID oid;
  RECDES forward_recdes;
  SCAN_CODE scan = S_ERROR;
  int get_rec_info = cache_recordinfo != NULL;
  bool is_null_recdata;
  PGBUF_WATCHER curr_page_watcher;
  PGBUF_WATCHER old_page_watcher;

  assert (scan_cache != NULL);

#if defined(CUBRID_DEBUG)
  if (scan_cache != NULL && scan_cache->debug_initpattern != HEAP_DEBUG_SCANCACHE_INITPATTERN)
    {
      er_log_debug (ARG_FILE_LINE, "heap_next: Your scancache is not initialized");
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      return S_ERROR;
    }
  if (scan_cache != NULL && HFID_IS_NULL (&scan_cache->hfid))
    {
      er_log_debug (ARG_FILE_LINE,
            "heap_next: scan_cache without heap.. heap file must be given to heap_scancache_start () when"
            " scan_cache is used with heap_first, heap_next, heap_prev heap_last");
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      return S_ERROR;
    }
#endif /* CUBRID_DEBUG */


  hfid = &scan_cache->node.hfid;
  if (!OID_ISNULL (&scan_cache->node.class_oid))
    {
      class_oid = &scan_cache->node.class_oid;
    }

  PGBUF_INIT_WATCHER (&curr_page_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&old_page_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  if (OID_ISNULL (next_oid))
    {
      if (reversed_direction)
    {
      /* Retrieve the last record of the file. */
      if (heap_get_last_vpid (thread_p, hfid, &vpid) != NO_ERROR)
        {
          ASSERT_ERROR ();
          return S_ERROR;
        }
      oid.volid = vpid.volid;
      oid.pageid = vpid.pageid;
      oid.slotid = NULL_SLOTID;
    }
      else
    {
      /* Retrieve the first object of the heap */
      oid.volid = hfid->vfid.volid;
      oid.pageid = hfid->hpgid;
      oid.slotid = 0;   /* i.e., will get slot 1 */
    }
    }
  else
    {
      oid = *next_oid;
    }


  is_null_recdata = (recdes->data == NULL);

  /* Start looking for next object */
  while (true)
    {
      /* Start looking for next object in current page. If we reach the end of this page without finding a new object,
       * fetch next page and continue looking there. If no objects are found, end scanning */
      while (true)
    {
      vpid.volid = oid.volid;
      vpid.pageid = oid.pageid;

      /* 
       * Fetch the page where the object of OID is stored. Use previous
       * scan page whenever possible, otherwise, deallocate the page.
       */
      if (scan_cache->cache_last_fix_page == true && scan_cache->page_watcher.pgptr != NULL)
        {
          vpidptr_incache = pgbuf_get_vpid_ptr (scan_cache->page_watcher.pgptr);
          if (VPID_EQ (&vpid, vpidptr_incache))
        {
          /* replace with local watcher, scan cache watcher will be changed by called functions */
          pgbuf_replace_watcher (thread_p, &scan_cache->page_watcher, &curr_page_watcher);
        }
          else
        {
          /* Keep previous scan page fixed until we fixed the current one */
          pgbuf_replace_watcher (thread_p, &scan_cache->page_watcher, &old_page_watcher);
        }
        }
      if (curr_page_watcher.pgptr == NULL)
        {
          curr_page_watcher.pgptr =
        heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE_PREVENT_DEALLOC, S_LOCK, scan_cache,
                         &curr_page_watcher);
          if (old_page_watcher.pgptr != NULL)
        {
          pgbuf_ordered_unfix (thread_p, &old_page_watcher);
        }
          if (curr_page_watcher.pgptr == NULL)
        {
          if (er_errid () == ER_PB_BAD_PAGEID)
            {
              er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, oid.volid, oid.pageid,
                  oid.slotid);
            }

          /* something went wrong, return */
          assert (scan_cache->page_watcher.pgptr == NULL);
          return S_ERROR;
        }
        }

      if (get_rec_info)
        {
          /* Getting record information means that we need to scan all slots even if they store no object. */
          if (reversed_direction)
        {
          scan =
            spage_previous_record_dont_skip_empty (curr_page_watcher.pgptr, &oid.slotid, &forward_recdes, PEEK);
        }
          else
        {
          scan =
            spage_next_record_dont_skip_empty (curr_page_watcher.pgptr, &oid.slotid, &forward_recdes, PEEK);
        }
          if (oid.slotid == HEAP_HEADER_AND_CHAIN_SLOTID)
        {
          /* skip the header */
          scan =
            spage_next_record_dont_skip_empty (curr_page_watcher.pgptr, &oid.slotid, &forward_recdes, PEEK);
        }
        }
      else
        {
          /* Find the next object. Skip relocated records (i.e., new_home records). This records must be accessed
           * through the relocation record (i.e., the object). */

          while (true)
        {
          if (reversed_direction)
            {
              scan = spage_previous_record (curr_page_watcher.pgptr, &oid.slotid, &forward_recdes, PEEK);
            }
          else
            {
              scan = spage_next_record (curr_page_watcher.pgptr, &oid.slotid, &forward_recdes, PEEK);
            }
          if (scan != S_SUCCESS)
            {
              /* stop */
              break;
            }
          if (oid.slotid == HEAP_HEADER_AND_CHAIN_SLOTID)
            {
              /* skip the header */
              continue;
            }
          type = spage_get_record_type (curr_page_watcher.pgptr, oid.slotid);
          if (type == REC_NEWHOME || type == REC_ASSIGN_ADDRESS || type == REC_UNKNOWN)
            {
              /* skip */
              continue;
            }

          break;
        }
        }

      if (scan != S_SUCCESS)
        {
          if (scan == S_END)
        {
          /* Find next page of heap and continue scanning */
          if (reversed_direction)
            {
              (void) heap_vpid_prev (thread_p, hfid, curr_page_watcher.pgptr, &vpid);
            }
          else
            {
              (void) heap_vpid_next (thread_p, hfid, curr_page_watcher.pgptr, &vpid);
            }
          pgbuf_replace_watcher (thread_p, &curr_page_watcher, &old_page_watcher);
          oid.volid = vpid.volid;
          oid.pageid = vpid.pageid;
          oid.slotid = -1;
          if (oid.pageid == NULL_PAGEID)
            {
              /* must be last page, end scanning */
              OID_SET_NULL (next_oid);
              if (old_page_watcher.pgptr != NULL)
            {
              pgbuf_ordered_unfix (thread_p, &old_page_watcher);
            }
              return scan;
            }
        }
          else
        {
          /* Error, stop scanning */
          if (old_page_watcher.pgptr != NULL)
            {
              pgbuf_ordered_unfix (thread_p, &old_page_watcher);
            }
          pgbuf_ordered_unfix (thread_p, &curr_page_watcher);
          return scan;
        }
        }
      else
        {
          /* found a new object */
          break;
        }
    }

      /* A record was found */
      if (get_rec_info)
    {
      scan =
        heap_get_record_info (thread_p, oid, recdes, forward_recdes, &curr_page_watcher, scan_cache, ispeeking,
                  cache_recordinfo);
    }
      else
    {
      int cache_last_fix_page_save = scan_cache->cache_last_fix_page;

      scan_cache->cache_last_fix_page = true;
      pgbuf_replace_watcher (thread_p, &curr_page_watcher, &scan_cache->page_watcher);

      scan = heap_scan_get_visible_version (thread_p, &oid, class_oid, recdes, scan_cache, ispeeking, NULL_CHN);
      scan_cache->cache_last_fix_page = cache_last_fix_page_save;

      if (!cache_last_fix_page_save && scan_cache->page_watcher.pgptr)
        {
          /* restore into curr_page_watcher and unfix later */
          pgbuf_replace_watcher (thread_p, &scan_cache->page_watcher, &curr_page_watcher);
        }
    }

      if (scan == S_SUCCESS)
    {
      /* 
       * Make sure that the found object is an instance of the desired
       * class. If it isn't then continue looking.
       */
      if (class_oid == NULL || OID_ISNULL (class_oid) || !OID_IS_ROOTOID (&oid))
        {
          /* stop */
          *next_oid = oid;
          break;
        }
      else
        {
          /* continue looking */
          if (is_null_recdata)
        {
          /* reset recdes->data before getting next record */
          recdes->data = NULL;
        }
          continue;
        }
    }
      else if (scan == S_SNAPSHOT_NOT_SATISFIED || scan == S_DOESNT_EXIST)
    {
      /* the record does not satisfies snapshot or was deleted - continue */
      if (is_null_recdata)
        {
          /* reset recdes->data before getting next record */
          recdes->data = NULL;
        }
      continue;
    }

      /* scan was not successful, stop scanning */
      break;
    }

  if (old_page_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_page_watcher);
    }

  if (curr_page_watcher.pgptr != NULL)
    {
      if (!scan_cache->cache_last_fix_page)
    {
      pgbuf_ordered_unfix (thread_p, &curr_page_watcher);
    }
      else
    {
      pgbuf_replace_watcher (thread_p, &curr_page_watcher, &scan_cache->page_watcher);
    }
    }

  return scan;
}

/*
 * heap_first () - Retrieve or peek first object of heap
 *   return: SCAN_CODE (Either of S_SUCCESS, S_DOESNT_FIT, S_END, S_ERROR)
 *   hfid(in):
 *   class_oid(in):
 *   oid(in/out): Object identifier of current record.
 *                Will be set to first available record or NULL_OID when there
 *                is not one.
 *   recdes(in/out): Pointer to a record descriptor. Will be modified to
 *                   describe the new record.
 *   scan_cache(in/out): Scan cache or NULL
 *   ispeeking(in): PEEK when the object is peeked, scan_cache cannot be NULL
 *                  COPY when the object is copied
 *
 */
SCAN_CODE
heap_first (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, OID * oid, RECDES * recdes,
        HEAP_SCANCACHE * scan_cache, int ispeeking)
{
  /* Retrieve the first record of the file */
  OID_SET_NULL (oid);
  oid->volid = hfid->vfid.volid;

  return heap_next (thread_p, hfid, class_oid, oid, recdes, scan_cache, ispeeking);
}

/*
 * heap_last () - Retrieve or peek last object of heap
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_DOESNT_FIT, S_END,
 *                      S_ERROR)
 *   hfid(in):
 *   class_oid(in):
 *   oid(in/out): Object identifier of current record.
 *                Will be set to last available record or NULL_OID when there is
 *                not one.
 *   recdes(in/out): Pointer to a record descriptor. Will be modified to
 *                   describe the new record.
 *   scan_cache(in/out): Scan cache or NULL
 *   ispeeking(in): PEEK when the object is peeked, scan_cache cannot be NULL
 *                  COPY when the object is copied
 *
 */
SCAN_CODE
heap_last (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, OID * oid, RECDES * recdes,
       HEAP_SCANCACHE * scan_cache, int ispeeking)
{
  /* Retrieve the first record of the file */
  OID_SET_NULL (oid);
  oid->volid = hfid->vfid.volid;

  return heap_prev (thread_p, hfid, class_oid, oid, recdes, scan_cache, ispeeking);
}

#if defined (ENABLE_UNUSED_FUNCTION)
/*
 * heap_cmp () - Compare heap object with current content
 *   return: int (> 0 recdes is larger,
 *                     < 0 recdes is smaller, and
 *                     = 0 same)
 *   oid(in): The object to compare
 *   recdes(in): Compare object against this content
 *
 * Note: Compare the heap object against given content in ASCII format.
 */
int
heap_cmp (THREAD_ENTRY * thread_p, const OID * oid, RECDES * recdes)
{
  HEAP_SCANCACHE scan_cache;
  RECDES peek_recdes;
  int compare;

  heap_scancache_quick_start (&scan_cache);
  if (heap_get (thread_p, oid, &peek_recdes, &scan_cache, PEEK, NULL_CHN) != S_SUCCESS)
    {
      compare = 1;
    }
  else if (recdes->length > peek_recdes.length)
    {
      compare = memcmp (recdes->data, peek_recdes.data, peek_recdes.length);
      if (compare == 0)
    {
      compare = 1;
    }
    }
  else
    {
      compare = memcmp (recdes->data, peek_recdes.data, recdes->length);
      if (compare == 0 && recdes->length != peek_recdes.length)
    {
      compare = -1;
    }
    }

  heap_scancache_end (thread_p, &scan_cache);

  return compare;
}
#endif /* ENABLE_UNUSED_FUNCTION */

/*
 * heap_scanrange_start () - Initialize a scanrange cursor
 *   return: NO_ERROR
 *   scan_range(in/out): Scan range
 *   hfid(in): Heap file identifier
 *   class_oid(in): Class identifier
 *                  For any class, NULL or NULL_OID can be given
 *
 * Note: A scanrange structure is initialized. The scanrange structure
 * is used to define a scan range (set of objects) and to cache
 * information about the latest fetched page and memory allocated
 * by the scan functions. This information is used in future
 * scans, for example, to avoid hashing for the same page in the
 * page buffer pool or defining another allocation area.
 * The caller is responsible for declaring the end of a scan
 * range so that the fixed pages and allocated memory are freed.
 * Using many scans at the same time should be avoided since page
 * buffers are fixed and locked for future references and there
 * is a limit of buffers in the page buffer pool. This is
 * analogous to fetching many pages at the same time.
 */
int
heap_scanrange_start (THREAD_ENTRY * thread_p, HEAP_SCANRANGE * scan_range, const HFID * hfid, const OID * class_oid,
              MVCC_SNAPSHOT * mvcc_snapshot)
{
  int ret = NO_ERROR;

  /* Start the scan cache */
  ret = heap_scancache_start (thread_p, &scan_range->scan_cache, hfid, class_oid, true, false, mvcc_snapshot);
  if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }

  OID_SET_NULL (&scan_range->first_oid);
  scan_range->first_oid.volid = hfid->vfid.volid;
  scan_range->last_oid = scan_range->first_oid;

  return ret;

exit_on_error:

  OID_SET_NULL (&scan_range->first_oid);
  OID_SET_NULL (&scan_range->last_oid);

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_scanrange_end () - End of a scanrange
 *   return:
 *   scan_range(in/out): Scanrange
 *
 * Note: Any fixed heap page on the given scan is freed and any memory
 * allocated by this scan is also freed. The scan_range structure is undefined.
 */
void
heap_scanrange_end (THREAD_ENTRY * thread_p, HEAP_SCANRANGE * scan_range)
{
  /* Finish the scan cache */
  heap_scancache_end (thread_p, &scan_range->scan_cache);
  OID_SET_NULL (&scan_range->first_oid);
  OID_SET_NULL (&scan_range->last_oid);
}

/*
 * heap_scanrange_to_following () - Define the following scanrange
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_END, S_ERROR)
 *   scan_range(in/out): Scanrange
 *   start_oid(in): Desired OID for first element in the scanrange or NULL
 *
 * Note: The range of a scanrange is defined. The scanrange is defined
 * as follows:
 *              a: When start_oid == NULL, the first scanrange object is the
 *                 next object after the last object in the previous scanrange
 *              b: When start_oid is the same as a NULL_OID, the first object
 *                 is the first heap object.
 *              c: The first object in the scanrange is the given object.
 *              The last object in the scanrange is either the first object in
 *              the scanrange or the one after the first object which is not a
 *              relocated or multipage object.
 */
SCAN_CODE
heap_scanrange_to_following (THREAD_ENTRY * thread_p, HEAP_SCANRANGE * scan_range, OID * start_oid)
{
  SCAN_CODE scan;
  RECDES recdes;
  INT16 slotid;
  VPID *vpid;

  if (HEAP_DEBUG_ISVALID_SCANRANGE (scan_range) != DISK_VALID)
    {
      return S_ERROR;
    }

  if (start_oid != NULL)
    {
      if (OID_ISNULL (start_oid))
    {
      /* Scanrange starts at first heap object */
      scan =
        heap_first (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid,
            &scan_range->first_oid, &recdes, &scan_range->scan_cache, PEEK);
      if (scan != S_SUCCESS)
        {
          return scan;
        }
    }
      else
    {
      /* Scanrange starts with the given object */
      scan_range->first_oid = *start_oid;
      scan = heap_get_visible_version (thread_p, &scan_range->last_oid, &scan_range->scan_cache.node.class_oid,
                       &recdes, &scan_range->scan_cache, PEEK, NULL_CHN);
      if (scan != S_SUCCESS)
        {
          if (scan == S_DOESNT_EXIST || scan == S_SNAPSHOT_NOT_SATISFIED)
        {
          scan =
            heap_next (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid,
                   &scan_range->first_oid, &recdes, &scan_range->scan_cache, PEEK);
          if (scan != S_SUCCESS)
            {
              return scan;
            }
        }
          else
        {
          return scan;
        }
        }
    }
    }
  else
    {
      /* 
       * Scanrange ends with the prior object after the first object in the
       * the previous scanrange
       */
      scan_range->first_oid = scan_range->last_oid;
      scan =
    heap_next (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid,
           &scan_range->first_oid, &recdes, &scan_range->scan_cache, PEEK);
      if (scan != S_SUCCESS)
    {
      return scan;
    }
    }


  scan_range->last_oid = scan_range->first_oid;
  if (scan_range->scan_cache.page_watcher.pgptr != NULL
      && (vpid = pgbuf_get_vpid_ptr (scan_range->scan_cache.page_watcher.pgptr)) != NULL
      && (vpid->pageid == scan_range->last_oid.pageid) && (vpid->volid == scan_range->last_oid.volid)
      && spage_get_record_type (scan_range->scan_cache.page_watcher.pgptr, scan_range->last_oid.slotid) == REC_HOME)
    {
      slotid = scan_range->last_oid.slotid;
      while (true)
    {
      if (spage_next_record (scan_range->scan_cache.page_watcher.pgptr, &slotid, &recdes, PEEK) != S_SUCCESS
          || spage_get_record_type (scan_range->scan_cache.page_watcher.pgptr, slotid) != REC_HOME)
        {
          break;
        }
      else
        {
          scan_range->last_oid.slotid = slotid;
        }
    }
    }

  return scan;
}

/*
 * heap_scanrange_to_prior () - Define the prior scanrange
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_END, S_ERROR)
 *   scan_range(in/out): Scanrange
 *   last_oid(in): Desired OID for first element in the scanrange or NULL
 *
 * Note: The range of a scanrange is defined. The scanrange is defined
 * as follows:
 *              a: When last_oid == NULL, the last scanrange object is the
 *                 prior object after the first object in the previous
 *                 scanrange.
 *              b: When last_oid is the same as a NULL_OID, the last object is
 *                 is the last heap object.
 *              c: The last object in the scanrange is the given object.
 *              The first object in the scanrange is either the last object in
 *              the scanrange or the one before the first object which is not
 *              a relocated or multipage object.
 */
SCAN_CODE
heap_scanrange_to_prior (THREAD_ENTRY * thread_p, HEAP_SCANRANGE * scan_range, OID * last_oid)
{
  SCAN_CODE scan;
  RECDES recdes;
  INT16 slotid;

  if (HEAP_DEBUG_ISVALID_SCANRANGE (scan_range) != DISK_VALID)
    {
      return S_ERROR;
    }

  if (last_oid != NULL)
    {
      if (OID_ISNULL (last_oid))
    {
      /* Scanrange ends at last heap object */
      scan =
        heap_last (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid,
               &scan_range->last_oid, &recdes, &scan_range->scan_cache, PEEK);
      if (scan != S_SUCCESS)
        {
          return scan;
        }
    }
      else
    {
      /* Scanrange ends with the given object */
      scan_range->last_oid = *last_oid;
      scan =
        heap_get_visible_version (thread_p, &scan_range->last_oid, &scan_range->scan_cache.node.class_oid, &recdes,
                      &scan_range->scan_cache, PEEK, NULL_CHN);
      if (scan != S_SUCCESS)
        {
          if (scan == S_DOESNT_EXIST || scan == S_SNAPSHOT_NOT_SATISFIED)
        {
          scan =
            heap_prev (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid,
                   &scan_range->first_oid, &recdes, &scan_range->scan_cache, PEEK);
          if (scan != S_SUCCESS)
            {
              return scan;
            }
        }
        }
    }
    }
  else
    {
      /* 
       * Scanrange ends with the prior object after the first object in the
       * the previous scanrange
       */
      scan_range->last_oid = scan_range->first_oid;
      scan =
    heap_prev (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid,
           &scan_range->last_oid, &recdes, &scan_range->scan_cache, PEEK);
      if (scan != S_SUCCESS)
    {
      return scan;
    }
    }

  /* 
   * Now define the first object for the scanrange. A scanrange range starts
   * when a relocated or multipage object is found or when the last object is
   * the page is found.
   */

  scan_range->first_oid = scan_range->last_oid;
  if (scan_range->scan_cache.page_watcher.pgptr != NULL)
    {
      slotid = scan_range->first_oid.slotid;
      while (true)
    {
      if (spage_previous_record (scan_range->scan_cache.page_watcher.pgptr, &slotid, &recdes, PEEK) != S_SUCCESS
          || slotid == HEAP_HEADER_AND_CHAIN_SLOTID
          || spage_get_record_type (scan_range->scan_cache.page_watcher.pgptr, slotid) != REC_HOME)
        {
          break;
        }
      else
        {
          scan_range->first_oid.slotid = slotid;
        }
    }
    }

  return scan;
}

/*
 * heap_scanrange_next () - Retrieve or peek next object in the scanrange
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_DOESNT_FIT, S_END,
 *                      S_ERROR)
 *   next_oid(in/out): Object identifier of current record.
 *                     Will be set to next available record or NULL_OID when
 *                     there is not one.
 *   recdes(in/out): Pointer to a record descriptor. Will be modified to
 *                   describe the new record.
 *   scan_range(in/out): Scan range ... Cannot be NULL
 *   ispeeking(in): PEEK when the object is peeked,
 *                  COPY when the object is copied
 *
 */
SCAN_CODE
heap_scanrange_next (THREAD_ENTRY * thread_p, OID * next_oid, RECDES * recdes, HEAP_SCANRANGE * scan_range,
             int ispeeking)
{
  SCAN_CODE scan;

  if (HEAP_DEBUG_ISVALID_SCANRANGE (scan_range) != DISK_VALID)
    {
      return S_ERROR;
    }

  /* 
   * If next_oid is less than the first OID in the scanrange.. get the first
   * object
   */

  if (OID_ISNULL (next_oid) || OID_LT (next_oid, &scan_range->first_oid))
    {
      /* Retrieve the first object in the scanrange */
      *next_oid = scan_range->first_oid;
      scan =
    heap_get_visible_version (thread_p, next_oid, &scan_range->scan_cache.node.class_oid, recdes,
                  &scan_range->scan_cache, ispeeking, NULL_CHN);
      if (scan == S_DOESNT_EXIST || scan == S_SNAPSHOT_NOT_SATISFIED)
    {
      scan =
        heap_next (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid, next_oid,
               recdes, &scan_range->scan_cache, ispeeking);
    }
      /* Make sure that we did not go overboard */
      if (scan == S_SUCCESS && OID_GT (next_oid, &scan_range->last_oid))
    {
      OID_SET_NULL (next_oid);
      scan = S_END;
    }
    }
  else
    {
      /* Make sure that this is not the last OID in the scanrange */
      if (OID_EQ (next_oid, &scan_range->last_oid))
    {
      OID_SET_NULL (next_oid);
      scan = S_END;
    }
      else
    {
      scan =
        heap_next (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid, next_oid,
               recdes, &scan_range->scan_cache, ispeeking);
      /* Make sure that we did not go overboard */
      if (scan == S_SUCCESS && OID_GT (next_oid, &scan_range->last_oid))
        {
          OID_SET_NULL (next_oid);
          scan = S_END;
        }
    }
    }

  return scan;
}

#if defined (ENABLE_UNUSED_FUNCTION)
/*
 * heap_scanrange_prev () - RETRIEVE OR PEEK NEXT OBJECT IN THE SCANRANGE
 *   return:
 * returns/side-effects: SCAN_CODE
 *              (Either of S_SUCCESS, S_DOESNT_FIT, S_END,
 *                         S_ERROR)
 *   prev_oid(in/out): Object identifier of current record.
 *                     Will be set to previous available record or NULL_OID when
 *                     there is not one.
 *   recdes(in/out): Pointer to a record descriptor. Will be modified to
 *                   describe the new record.
 *   scan_range(in/out): Scan range ... Cannot be NULL
 *   ispeeking(in): PEEK when the object is peeked,
 *                  COPY when the object is copied
 *
 */
SCAN_CODE
heap_scanrange_prev (THREAD_ENTRY * thread_p, OID * prev_oid, RECDES * recdes, HEAP_SCANRANGE * scan_range,
             int ispeeking)
{
  SCAN_CODE scan;

  if (HEAP_DEBUG_ISVALID_SCANRANGE (scan_range) != DISK_VALID)
    {
      return S_ERROR;
    }

  if (OID_ISNULL (prev_oid) || OID_GT (prev_oid, &scan_range->last_oid))
    {
      /* Retrieve the last object in the scanrange */
      *prev_oid = scan_range->last_oid;
      scan = heap_get (thread_p, prev_oid, recdes, &scan_range->scan_cache, ispeeking, NULL_CHN);
      if (scan == S_DOESNT_EXIST || scan == S_SNAPSHOT_NOT_SATISFIED)
    {
      scan =
        heap_prev (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid, prev_oid,
               recdes, &scan_range->scan_cache, ispeeking);
    }
      /* Make sure that we did not go underboard */
      if (scan == S_SUCCESS && OID_LT (prev_oid, &scan_range->last_oid))
    {
      OID_SET_NULL (prev_oid);
      scan = S_END;
    }
    }
  else
    {
      /* Make sure that this is not the first OID in the scanrange */
      if (OID_EQ (prev_oid, &scan_range->first_oid))
    {
      OID_SET_NULL (prev_oid);
      scan = S_END;
    }
      else
    {
      scan =
        heap_prev (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid, prev_oid,
               recdes, &scan_range->scan_cache, ispeeking);
      if (scan == S_SUCCESS && OID_LT (prev_oid, &scan_range->last_oid))
        {
          OID_SET_NULL (prev_oid);
          scan = S_END;
        }
    }
    }

  return scan;
}

/*
 * heap_scanrange_first () - Retrieve or peek first object in the scanrange
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_DOESNT_FIT, S_END,
 *                      S_ERROR)
 *   first_oid(in/out): Object identifier.
 *                      Set to first available record or NULL_OID when there
 *                      is not one.
 *   recdes(in/out): Pointer to a record descriptor. Will be modified to
 *                   describe the new record.
 *   scan_range(in/out): Scan range ... Cannot be NULL
 *   ispeeking(in): PEEK when the object is peeked,
 *                  COPY when the object is copied
 *
 */
SCAN_CODE
heap_scanrange_first (THREAD_ENTRY * thread_p, OID * first_oid, RECDES * recdes, HEAP_SCANRANGE * scan_range,
              int ispeeking)
{
  SCAN_CODE scan;

  if (HEAP_DEBUG_ISVALID_SCANRANGE (scan_range) != DISK_VALID)
    {
      return S_ERROR;
    }

  /* Retrieve the first object in the scanrange */
  *first_oid = scan_range->first_oid;
  scan = heap_get (thread_p, first_oid, recdes, &scan_range->scan_cache, ispeeking, NULL_CHN);
  if (scan == S_DOESNT_EXIST || scan == S_SNAPSHOT_NOT_SATISFIED)
    {
      scan =
    heap_next (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid, first_oid,
           recdes, &scan_range->scan_cache, ispeeking);
    }
  /* Make sure that we did not go overboard */
  if (scan == S_SUCCESS && OID_GT (first_oid, &scan_range->last_oid))
    {
      OID_SET_NULL (first_oid);
      scan = S_END;
    }

  return scan;
}

/*
 * heap_scanrange_last () - Retrieve or peek last object in the scanrange
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_DOESNT_FIT, S_END,
 *                      S_ERROR)
 *   last_oid(in/out): Object identifier.
 *                     Set to last available record or NULL_OID when there is
 *                     not one
 *   recdes(in/out): Pointer to a record descriptor. Will be modified to
 *                   describe the new record.
 *   scan_range(in/out): Scan range ... Cannot be NULL
 *   ispeeking(in): PEEK when the object is peeked,
 *                  COPY when the object is copied
 *
 */
SCAN_CODE
heap_scanrange_last (THREAD_ENTRY * thread_p, OID * last_oid, RECDES * recdes, HEAP_SCANRANGE * scan_range,
             int ispeeking)
{
  SCAN_CODE scan;

  if (HEAP_DEBUG_ISVALID_SCANRANGE (scan_range) != DISK_VALID)
    {
      return S_ERROR;
    }

  /* Retrieve the last object in the scanrange */
  *last_oid = scan_range->last_oid;
  scan = heap_get (thread_p, last_oid, recdes, &scan_range->scan_cache, ispeeking, NULL_CHN);
  if (scan == S_DOESNT_EXIST || scan == S_SNAPSHOT_NOT_SATISFIED)
    {
      scan =
    heap_prev (thread_p, &scan_range->scan_cache.node.hfid, &scan_range->scan_cache.node.class_oid, last_oid,
           recdes, &scan_range->scan_cache, ispeeking);
    }
  /* Make sure that we did not go underboard */
  if (scan == S_SUCCESS && OID_LT (last_oid, &scan_range->last_oid))
    {
      OID_SET_NULL (last_oid);
      scan = S_END;
    }

  return scan;
}
#endif

/*
 * heap_does_exist () - Does object exist?
 *   return: true/false
 *   class_oid(in): Class identifier of object or NULL
 *   oid(in): Object identifier
 *
 * Note: Check if the object associated with the given OID exist.
 * If the class of the object does not exist, the object does not
 * exist either. If the class is not given or a NULL_OID is
 * passed, the function finds the class oid.
 */
bool
heap_does_exist (THREAD_ENTRY * thread_p, OID * class_oid, const OID * oid)
{
  VPID vpid;
  OID tmp_oid;
  PGBUF_WATCHER pg_watcher;
  bool doesexist = true;
  INT16 rectype;
  bool old_check_interrupt;
  int old_wait_msec;

  PGBUF_INIT_WATCHER (&pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, PGBUF_ORDERED_NULL_HFID);

  old_check_interrupt = logtb_set_check_interrupt (thread_p, false);
  old_wait_msec = xlogtb_reset_wait_msecs (thread_p, LK_INFINITE_WAIT);

  if (HEAP_ISVALID_OID (thread_p, oid) != DISK_VALID)
    {
      doesexist = false;
      goto exit_on_end;
    }

  /* 
   * If the class is not NULL and it is different from the Rootclass,
   * make sure that it exist. Rootclass always exist.. not need to check
   * for it
   */
  if (class_oid != NULL && !OID_EQ (class_oid, oid_Root_class_oid)
      && HEAP_ISVALID_OID (thread_p, class_oid) != DISK_VALID)
    {
      doesexist = false;
      goto exit_on_end;
    }

  while (doesexist)
    {
      if (oid->slotid == HEAP_HEADER_AND_CHAIN_SLOTID || oid->slotid < 0 || oid->pageid < 0 || oid->volid < 0)
    {
      doesexist = false;
      goto exit_on_end;
    }

      vpid.volid = oid->volid;
      vpid.pageid = oid->pageid;

      /* Fetch the page where the record is stored */

      pg_watcher.pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, S_LOCK, NULL, &pg_watcher);
      if (pg_watcher.pgptr == NULL)
    {
      if (er_errid () == ER_PB_BAD_PAGEID)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, oid->volid, oid->pageid,
              oid->slotid);
        }

      /* something went wrong, give up */
      doesexist = false;
      goto exit_on_end;
    }

      doesexist = spage_is_slot_exist (pg_watcher.pgptr, oid->slotid);
      rectype = spage_get_record_type (pg_watcher.pgptr, oid->slotid);

      /* 
       * Check the class
       */

      if (doesexist && rectype != REC_ASSIGN_ADDRESS)
    {
      if (class_oid == NULL)
        {
          class_oid = &tmp_oid;
          OID_SET_NULL (class_oid);
        }

      if (OID_ISNULL (class_oid))
        {
          /* 
           * Caller does not know the class of the object. Get the class
           * identifier from disk
           */
          if (heap_get_class_oid_from_page (thread_p, pg_watcher.pgptr, class_oid) != NO_ERROR)
        {
          assert_release (false);
          doesexist = false;
          goto exit_on_end;
        }
          assert (!OID_ISNULL (class_oid));
        }

      pgbuf_ordered_unfix (thread_p, &pg_watcher);

      /* If doesexist is true, then check its class */
      if (!OID_IS_ROOTOID (class_oid))
        {
          /* 
           * Make sure that the class exist too. Loop with this
           */
          oid = class_oid;
          class_oid = oid_Root_class_oid;
        }
      else
        {
          break;
        }
    }
      else
    {
      break;
    }
    }

exit_on_end:

  if (pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
    }

  (void) logtb_set_check_interrupt (thread_p, old_check_interrupt);
  (void) xlogtb_reset_wait_msecs (thread_p, old_wait_msec);

  return doesexist;
}

/*
 * heap_is_object_not_null () - Check if object should be considered not NULL.
 *
 * return     : True if object is visible or too new, false if it is deleted or if errors occur.
 * thread_p (in)  : Thread entry.
 * class_oid (in) : Class OID.
 * oid (in)   : Instance OID.
 */
bool
heap_is_object_not_null (THREAD_ENTRY * thread_p, OID * class_oid, const OID * oid)
{
  bool old_check_interrupt = logtb_set_check_interrupt (thread_p, false);
  bool doesexist = false;
  HEAP_SCANCACHE scan_cache;
  SCAN_CODE scan = S_SUCCESS;
  OID local_class_oid = OID_INITIALIZER;
  MVCC_SNAPSHOT *mvcc_snapshot_ptr;
  MVCC_SNAPSHOT copy_mvcc_snapshot;
  bool is_scancache_started = false;

  er_stack_push ();

  if (HEAP_ISVALID_OID (thread_p, oid) != DISK_VALID)
    {
      goto exit_on_end;
    }

  /* 
   * If the class is not NULL and it is different from the Root class,
   * make sure that it exist. Root class always exist.. not need to check for it
   */
  if (class_oid != NULL && !OID_EQ (class_oid, oid_Root_class_oid)
      && HEAP_ISVALID_OID (thread_p, class_oid) != DISK_VALID)
    {
      goto exit_on_end;
    }
  if (class_oid == NULL)
    {
      class_oid = &local_class_oid;
    }

  if (heap_scancache_quick_start (&scan_cache) != NO_ERROR)
    {
      goto exit_on_end;
    }
  is_scancache_started = true;

  mvcc_snapshot_ptr = logtb_get_mvcc_snapshot (thread_p);
  if (mvcc_snapshot_ptr == NULL)
    {
      assert (false);
      goto exit_on_end;
    }
  /* Make a copy of snapshot. We need all MVCC information, but we also want to change the visibility function. */
  copy_mvcc_snapshot = *mvcc_snapshot_ptr;
  copy_mvcc_snapshot.snapshot_fnc = mvcc_is_not_deleted_for_snapshot;
  scan_cache.mvcc_snapshot = &copy_mvcc_snapshot;

  /* Check only if the last version of the object is not deleted, see mvcc_is_not_deleted_for_snapshot return values */
  scan = heap_get_visible_version (thread_p, oid, class_oid, NULL, &scan_cache, PEEK, NULL_CHN);
  if (scan != S_SUCCESS)
    {
      goto exit_on_end;
    }
  assert (!OID_ISNULL (class_oid));

  /* Check class exists. */
  doesexist = heap_does_exist (thread_p, oid_Root_class_oid, class_oid);

exit_on_end:
  (void) logtb_set_check_interrupt (thread_p, old_check_interrupt);

  if (is_scancache_started)
    {
      heap_scancache_end (thread_p, &scan_cache);
    }

  /* We don't need to propagate errors from here. */
  er_stack_pop ();

  return doesexist;
}

/*
 * heap_get_num_objects () - Count the number of objects
 *   return: number of records or -1 in case of an error
 *   hfid(in): Object heap file identifier
 *   npages(in):
 *   nobjs(in):
 *   avg_length(in):
 *
 * Note: Count the number of objects stored on the given heap.
 * This function is expensive since all pages of the heap are
 * fetched to find the number of objects.
 */
int
heap_get_num_objects (THREAD_ENTRY * thread_p, const HFID * hfid, int *npages, int *nobjs, int *avg_length)
{
  VPID vpid;            /* Page-volume identifier */
  LOG_DATA_ADDR addr_hdr;   /* Address of logging data */
  RECDES hdr_recdes;        /* Record descriptor to point to space statistics */
  HEAP_HDR_STATS *heap_hdr; /* Heap header */
  PGBUF_WATCHER hdr_pg_watcher;

  /* 
   * Get the heap header in exclusive mode and call the synchronization to
   * update the statistics of the heap. The number of record/objects is
   * updated.
   */

  PGBUF_INIT_WATCHER (&hdr_pg_watcher, PGBUF_ORDERED_HEAP_HDR, hfid);

  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;

  addr_hdr.vfid = &hfid->vfid;
  addr_hdr.offset = HEAP_HEADER_AND_CHAIN_SLOTID;

  if (pgbuf_ordered_fix (thread_p, &vpid, OLD_PAGE, PGBUF_LATCH_WRITE, &hdr_pg_watcher) != NO_ERROR)
    {
      return ER_FAILED;
    }

  (void) pgbuf_check_page_ptype (thread_p, hdr_pg_watcher.pgptr, PAGE_HEAP);

  if (spage_get_record (thread_p, hdr_pg_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &hdr_recdes, PEEK) != S_SUCCESS)
    {
      pgbuf_ordered_unfix (thread_p, &hdr_pg_watcher);
      return ER_FAILED;
    }

  heap_hdr = (HEAP_HDR_STATS *) hdr_recdes.data;
  if (heap_stats_sync_bestspace (thread_p, hfid, heap_hdr, pgbuf_get_vpid_ptr (hdr_pg_watcher.pgptr), true, true) < 0)
    {
      pgbuf_ordered_unfix (thread_p, &hdr_pg_watcher);
      return ER_FAILED;
    }
  *npages = heap_hdr->estimates.num_pages;
  *nobjs = heap_hdr->estimates.num_recs;
  if (*nobjs > 0)
    {
      *avg_length = (int) ((heap_hdr->estimates.recs_sumlen / (float) *nobjs) + 0.9);
    }
  else
    {
      *avg_length = 0;
    }

  addr_hdr.pgptr = hdr_pg_watcher.pgptr;
  log_skip_logging (thread_p, &addr_hdr);
  pgbuf_ordered_set_dirty_and_free (thread_p, &hdr_pg_watcher);

  return *nobjs;
}

/*
 * heap_estimate () - Estimate the number of pages, objects, average length
 *   return: number of pages estimated or -1 in case of an error
 *   hfid(in): Object heap file identifier
 *   npages(in):
 *   nobjs(in):
 *   avg_length(in):
 *
 * Note: Estimate the number of pages, objects, and average length of objects.
 */
int
heap_estimate (THREAD_ENTRY * thread_p, const HFID * hfid, int *npages, int *nobjs, int *avg_length)
{
  VPID vpid;            /* Page-volume identifier */
  PAGE_PTR hdr_pgptr = NULL;    /* Page pointer */
  RECDES hdr_recdes;        /* Record descriptor to point to space statistics */
  HEAP_HDR_STATS *heap_hdr; /* Heap header */

  /* 
   * Get the heap header in shared mode since it is an estimation of the
   * number of objects.
   */

  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;

  hdr_pgptr = pgbuf_fix (thread_p, &vpid, OLD_PAGE, PGBUF_LATCH_READ, PGBUF_UNCONDITIONAL_LATCH);
  if (hdr_pgptr == NULL)
    {
      /* something went wrong. Unable to fetch header page */
      return ER_FAILED;
    }

  (void) pgbuf_check_page_ptype (thread_p, hdr_pgptr, PAGE_HEAP);

  if (spage_get_record (thread_p, hdr_pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &hdr_recdes, PEEK) != S_SUCCESS)
    {
      pgbuf_unfix_and_init (thread_p, hdr_pgptr);
      return ER_FAILED;
    }

  heap_hdr = (HEAP_HDR_STATS *) hdr_recdes.data;
  *npages = heap_hdr->estimates.num_pages;
  *nobjs = heap_hdr->estimates.num_recs;
  if (*nobjs > 0)
    {
      *avg_length = (int) ((heap_hdr->estimates.recs_sumlen / (float) *nobjs) + 0.9);
    }
  else
    {
      *avg_length = 0;
    }

  pgbuf_unfix_and_init (thread_p, hdr_pgptr);

  return *npages;
}

/*
 * heap_estimate_num_objects () - Estimate the number of objects
 *   return: number of records estimated or -1 in case of an error
 *   hfid(in): Object heap file identifier
 *
 * Note: Estimate the number of objects stored on the given heap.
 */
int
heap_estimate_num_objects (THREAD_ENTRY * thread_p, const HFID * hfid)
{
  int ignore_npages = -1;
  int ignore_avg_reclen = -1;
  int nobjs = -1;

  if (heap_estimate (thread_p, hfid, &ignore_npages, &nobjs, &ignore_avg_reclen) == -1)
    {
      return ER_FAILED;
    }

  return nobjs;
}

/*
 * heap_estimate_avg_length () - Estimate the average length of records
 *   return: avg length
 *   hfid(in): Object heap file identifier
 *
 * Note: Estimate the avergae length of the objects stored on the heap.
 * This function is mainly used when we are creating the OID of
 * an object of which we do not know its length. Mainly for
 * loaddb during forward references to other objects.
 */
static int
heap_estimate_avg_length (THREAD_ENTRY * thread_p, const HFID * hfid)
{
  int ignore_npages;
  int ignore_nobjs;
  int avg_reclen;

  if (heap_estimate (thread_p, hfid, &ignore_npages, &ignore_nobjs, &avg_reclen) == -1)
    {
      return ER_FAILED;
    }

  return avg_reclen;
}

/*
 * heap_get_capacity () - Find space consumed by heap
 *   return: NO_ERROR
 *   hfid(in): Object heap file identifier
 *   num_recs(in/out): Total Number of objects
 *   num_recs_relocated(in/out):
 *   num_recs_inovf(in/out):
 *   num_pages(in/out): Total number of heap pages
 *   avg_freespace(in/out): Average free space per page
 *   avg_freespace_nolast(in/out): Average free space per page without taking in
 *                                 consideration last page
 *   avg_reclength(in/out): Average object length
 *   avg_overhead(in/out): Average overhead per page
 *
 * Note: Find the current storage facts/capacity for given heap.
 */
static int
heap_get_capacity (THREAD_ENTRY * thread_p, const HFID * hfid, INT64 * num_recs, INT64 * num_recs_relocated,
           INT64 * num_recs_inovf, INT64 * num_pages, int *avg_freespace, int *avg_freespace_nolast,
           int *avg_reclength, int *avg_overhead)
{
  VPID vpid;            /* Page-volume identifier */
  RECDES recdes;        /* Header record descriptor */
  INT16 slotid;         /* Slot of one object */
  OID *ovf_oid;
  int last_freespace;
  int ovf_len;
  int ovf_num_pages;
  int ovf_free_space;
  int ovf_overhead;
  int j;
  INT16 type = REC_UNKNOWN;
  int ret = NO_ERROR;
  INT64 sum_freespace = 0;
  INT64 sum_reclength = 0;
  INT64 sum_overhead = 0;
  PGBUF_WATCHER pg_watcher;
  PGBUF_WATCHER old_pg_watcher;

  PGBUF_INIT_WATCHER (&pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&old_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  *num_recs = 0;
  *num_pages = 0;
  *avg_freespace = 0;
  *avg_reclength = 0;
  *avg_overhead = 0;
  *num_recs_relocated = 0;
  *num_recs_inovf = 0;
  last_freespace = 0;

  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;

  while (!VPID_ISNULL (&vpid))
    {
      pg_watcher.pgptr =
    heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE_PREVENT_DEALLOC, S_LOCK, NULL, &pg_watcher);
      if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }

      if (pg_watcher.pgptr == NULL)
    {
      /* something went wrong, return error */
      goto exit_on_error;
    }

      slotid = -1;
      j = spage_number_of_records (pg_watcher.pgptr);

      last_freespace = spage_get_free_space (thread_p, pg_watcher.pgptr);

      *num_pages += 1;
      sum_freespace += last_freespace;
      sum_overhead += j * spage_slot_size ();

      while ((j--) > 0)
    {
      if (spage_next_record (pg_watcher.pgptr, &slotid, &recdes, PEEK) == S_SUCCESS)
        {
          if (slotid != HEAP_HEADER_AND_CHAIN_SLOTID)
        {
          type = spage_get_record_type (pg_watcher.pgptr, slotid);
          switch (type)
            {
            case REC_RELOCATION:
              *num_recs_relocated += 1;
              sum_overhead += spage_get_record_length (thread_p, pg_watcher.pgptr, slotid);
              break;
            case REC_ASSIGN_ADDRESS:
            case REC_HOME:
            case REC_NEWHOME:
              /* 
               * Note: for newhome (relocated), we are including the length
               *       and number of records. In the relocation record (above)
               *       we are just adding the overhead and number of
               *       reclocation records.
               *       for assign address, we assume the given size.
               */
              *num_recs += 1;
              sum_reclength += spage_get_record_length (thread_p, pg_watcher.pgptr, slotid);
              break;
            case REC_BIGONE:
              *num_recs += 1;
              *num_recs_inovf += 1;
              sum_overhead += spage_get_record_length (thread_p, pg_watcher.pgptr, slotid);

              ovf_oid = (OID *) recdes.data;
              if (heap_ovf_get_capacity (thread_p, ovf_oid, &ovf_len, &ovf_num_pages, &ovf_overhead,
                         &ovf_free_space) == NO_ERROR)
            {
              sum_reclength += ovf_len;
              *num_pages += ovf_num_pages;
              sum_freespace += ovf_free_space;
              sum_overhead += ovf_overhead;
            }
              break;
            case REC_MARKDELETED:
              /* 
               * TODO Find out and document here why this is added to
               * the overhead. The record has been deleted so its
               * length should no longer have any meaning. Perhaps
               * the length of the slot should have been added instead?
               */
              sum_overhead += spage_get_record_length (thread_p, pg_watcher.pgptr, slotid);
              break;
            case REC_DELETED_WILL_REUSE:
            default:
              break;
            }
        }
        }
    }
      (void) heap_vpid_next (thread_p, hfid, pg_watcher.pgptr, &vpid);
      pgbuf_replace_watcher (thread_p, &pg_watcher, &old_pg_watcher);
    }

  if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }

  assert (pg_watcher.pgptr == NULL);

  if (*num_pages > 0)
    {
      /* 
       * Don't take in consideration the last page for free space
       * considerations since the average free space will be contaminated.
       */
      *avg_freespace_nolast = ((*num_pages > 1) ? (int) ((sum_freespace - last_freespace) / (*num_pages - 1)) : 0);
      *avg_freespace = (int) (sum_freespace / *num_pages);
      *avg_overhead = (int) (sum_overhead / *num_pages);
    }

  if (*num_recs != 0)
    {
      *avg_reclength = (int) (sum_reclength / *num_recs);
    }

  return ret;

exit_on_error:

  if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }
  assert (pg_watcher.pgptr == NULL);

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
* heap_get_class_oid () - Get class for object. This function doesn't follow
*              MVCC versions. Caller must know to use right
*              version for this.
*
* return       : Scan code.
* thread_p (in)   : Thread entry.
* oid (in)     : Object OID.
* class_oid (out) : Output class OID.
*/
SCAN_CODE
heap_get_class_oid (THREAD_ENTRY * thread_p, const OID * oid, OID * class_oid)
{
  PGBUF_WATCHER page_watcher;
  int err;

  PGBUF_INIT_WATCHER (&page_watcher, PGBUF_ORDERED_HEAP_NORMAL, PGBUF_ORDERED_NULL_HFID);

  assert (oid != NULL && !OID_ISNULL (oid) && class_oid != NULL);
  OID_SET_NULL (class_oid);

  err = heap_prepare_object_page (thread_p, oid, &page_watcher, PGBUF_LATCH_READ);
  if (err != NO_ERROR)
    {
      /* for non existent object, return S_DOESNT_EXIST and let the caller handle the case; */
      return err == ER_HEAP_UNKNOWN_OBJECT ? S_DOESNT_EXIST : S_ERROR;
    }

  /* Get class OID from HEAP_CHAIN. */
  if (heap_get_class_oid_from_page (thread_p, page_watcher.pgptr, class_oid) != NO_ERROR)
    {
      /* Unexpected. */
      assert_release (false);
      pgbuf_ordered_unfix (thread_p, &page_watcher);
      return S_ERROR;
    }

  pgbuf_ordered_unfix (thread_p, &page_watcher);
  return S_SUCCESS;
}

/*
 * heap_get_class_name () - Find classname when oid is a class
 *   return: error_code
 *
 *   class_oid(in): The Class Object identifier
 *   class_name(out): Reference of the Class name pointer where name will reside; 
 *            The classname space must be released by the caller.
 *
 * Note: Find the name of the given class identifier. It asserts that the given OID is class OID.
 *
 * Note: Classname pointer must be released by the caller using free_and_init
 */
int
heap_get_class_name (THREAD_ENTRY * thread_p, const OID * class_oid, char **class_name)
{
  return heap_get_class_name_alloc_if_diff (thread_p, class_oid, NULL, class_name);
}

/*
 * heap_get_class_name_alloc_if_diff () - Get the name of given class
 *                               name is malloc when different than given name
 *   return: error_code if error(other than ER_HEAP_NODATA_NEWADDRESS) occur
 *
 *   class_oid(in): The Class Object identifier
 *   guess_classname(in): Guess name of class
 *   classname_out(out):  guess_classname when it is the real name. Don't need to free.
 *            malloc classname when different from guess_classname.
 *            Must be free by caller (free_and_init)
 *            NULL in case of error
 *
 * Note: Find the name of the given class identifier. If the name is
 * the same as the guessed name, the guessed name is returned.
 * Otherwise, an allocated area with the name of the class is
 * returned. 
 */
int
heap_get_class_name_alloc_if_diff (THREAD_ENTRY * thread_p, const OID * class_oid, char *guess_classname,
                   char **classname_out)
{
  char *classname = NULL;
  RECDES recdes;
  HEAP_SCANCACHE scan_cache;
  int error_code = NO_ERROR;

  (void) heap_scancache_quick_start_root_hfid (thread_p, &scan_cache);

  if (heap_get_class_record (thread_p, class_oid, &recdes, &scan_cache, PEEK) == S_SUCCESS)
    {
      classname = or_class_name (&recdes);
      if (guess_classname == NULL || strcmp (guess_classname, classname) != 0)
    {
      /* 
       * The names are different.. return a copy that must be freed.
       */
      *classname_out = strdup (classname);
      if (*classname_out == NULL)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1,
              (strlen (classname) + 1) * sizeof (char));
          error_code = ER_FAILED;
        }
    }
      else
    {
      /* 
       * The classnames are identical
       */
      *classname_out = guess_classname;
    }
    }
  else
    {
      ASSERT_ERROR_AND_SET (error_code);
      *classname_out = NULL;
      if (error_code == ER_HEAP_NODATA_NEWADDRESS)
    {
      /* clear ER_HEAP_NODATA_NEWADDRESS */
      er_clear ();
      error_code = NO_ERROR;
    }
    }

  heap_scancache_end (thread_p, &scan_cache);

  return error_code;
}

/*
 * heap_attrinfo_start () - Initialize an attribute information structure
 *   return: NO_ERROR
 *   class_oid(in): The class identifier of the instances where values
 *                  attributes values are going to be read.
 *   requested_num_attrs(in): Number of requested attributes
 *                            If <=0 are given, it means interested on ALL.
 *   attrids(in): Array of requested attributes
 *   attr_info(in/out): The attribute information structure
 *
 * Note: Initialize an attribute information structure, so that values
 * of instances can be retrieved based on the desired attributes.
 * If the requested number of attributes is less than zero,
 * all attributes will be assumed instead. In this case
 * the attrids array should be NULL.
 *
 * The attrinfo structure is an structure where values of
 * instances can be read. For example an object is retrieved,
 * then some of its attributes are convereted to dbvalues and
 * placed in this structure.
 *
 * Note: The caller must call heap_attrinfo_end after he is done with
 * attribute information.
 */
int
heap_attrinfo_start (THREAD_ENTRY * thread_p, const OID * class_oid, int requested_num_attrs, const ATTR_ID * attrids,
             HEAP_CACHE_ATTRINFO * attr_info)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  bool getall;          /* Want all attribute values */
  int i;
  int ret = NO_ERROR;

  if (requested_num_attrs == 0)
    {
      /* initialize the attrinfo cache and return, there is nothing else to do */
      (void) memset (attr_info, '\0', sizeof (HEAP_CACHE_ATTRINFO));

      /* now set the num_values to -1 which indicates that this is an empty HEAP_CACHE_ATTRINFO and shouldn't be
       * operated on. */
      attr_info->num_values = -1;
      return NO_ERROR;
    }

  if (requested_num_attrs < 0)
    {
      getall = true;
    }
  else
    {
      getall = false;
    }

  /* 
   * initialize attribute information
   *
   */

  attr_info->class_oid = *class_oid;
  attr_info->last_cacheindex = -1;
  attr_info->read_cacheindex = -1;

  attr_info->last_classrepr = NULL;
  attr_info->read_classrepr = NULL;

  OID_SET_NULL (&attr_info->inst_oid);
  attr_info->inst_chn = NULL_CHN;
  attr_info->values = NULL;
  attr_info->num_values = -1;   /* initialize attr_info */

  /* 
   * Find the most recent representation of the instances of the class, and
   * cache the structure that describe the attributes of this representation.
   * At the same time find the default values of attributes, the shared
   * attribute values and the class attribute values.
   */

  attr_info->last_classrepr =
    heap_classrepr_get (thread_p, &attr_info->class_oid, NULL, NULL_REPRID, &attr_info->last_cacheindex);
  if (attr_info->last_classrepr == NULL)
    {
      goto exit_on_error;
    }

  /* 
   * If the requested attributes is < 0, get all attributes of the last
   * representation.
   */

  if (requested_num_attrs < 0)
    {
      requested_num_attrs = attr_info->last_classrepr->n_attributes;
    }
  else if (requested_num_attrs >
       (attr_info->last_classrepr->n_attributes + attr_info->last_classrepr->n_shared_attrs +
        attr_info->last_classrepr->n_class_attrs))
    {
      fprintf (stdout, " XXX There are not that many attributes. Num_attrs = %d, Num_requested_attrs = %d\n",
           attr_info->last_classrepr->n_attributes, requested_num_attrs);
      requested_num_attrs =
    attr_info->last_classrepr->n_attributes + attr_info->last_classrepr->n_shared_attrs +
    attr_info->last_classrepr->n_class_attrs;
    }

  if (requested_num_attrs > 0)
    {
      attr_info->values =
    (HEAP_ATTRVALUE *) db_private_alloc (thread_p, requested_num_attrs * sizeof (*(attr_info->values)));
      if (attr_info->values == NULL)
    {
      goto exit_on_error;
    }
    }
  else
    {
      attr_info->values = NULL;
    }

  attr_info->num_values = requested_num_attrs;

  /* 
   * Set the attribute identifier of the desired attributes in the value
   * attribute information, and indicates that the current value is
   * unitialized. That is, it has not been read, set or whatever.
   */

  for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      if (getall == true)
    {
      value->attrid = -1;
    }
      else
    {
      value->attrid = *attrids++;
    }
      value->state = HEAP_UNINIT_ATTRVALUE;
      value->do_increment = 0;
      value->last_attrepr = NULL;
      value->read_attrepr = NULL;
    }

  /* 
   * Make last information to be recached for each individual attribute
   * value. Needed for WRITE and Default values
   */

  if (heap_attrinfo_recache_attrepr (attr_info, true) != NO_ERROR)
    {
      goto exit_on_error;
    }

  return ret;

exit_on_error:

  heap_attrinfo_end (thread_p, attr_info);

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

#if 0               /* TODO: remove unused */
/*
 * heap_moreattr_attrinfo () - Add another attribute to the attribute information
 *                           cache
 *   return: NO_ERROR
 *   attrid(in): The information of the attribute that will be needed
 *   attr_info(in/out): The attribute information structure
 *
 * Note: The given attribute is included as part of the reading or
 * transformation process.
 */
static int
heap_moreattr_attrinfo (int attrid, HEAP_CACHE_ATTRINFO * attr_info)
{
  HEAP_ATTRVALUE *new_values;   /* The new value attribute array */
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int i;
  int ret = NO_ERROR;

  /* 
   * If we get an empty HEAP_CACHE_ATTRINFO, this is an error.  We can
   * not add more attributes to an improperly initialized HEAP_CACHE_ATTRINFO
   * structure.
   */
  if (attr_info->num_values == -1)
    {
      return ER_FAILED;
    }

  /* 
   * Make sure that the attribute is not already included
   */
  for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      if (value != NULL && value->attrid == attrid)
    {
      return NO_ERROR;
    }
    }

  /* 
   * Resize the value attribute array and set the attribute identifier as
   * as part of the desired attribute list
   */
  i = (attr_info->num_values + 1) * sizeof (*(attr_info->values));

  new_values = (HEAP_ATTRVALUE *) db_private_realloc (NULL, attr_info->values, i);
  if (new_values == NULL)
    {
      goto exit_on_error;
    }

  attr_info->values = new_values;

  value = &attr_info->values[attr_info->num_values];
  value->attrid = attrid;
  value->state = HEAP_UNINIT_ATTRVALUE;
  value->last_attrepr = NULL;
  value->read_attrepr = NULL;
  attr_info->num_values++;

  /* 
   * Recache attribute representation and get default value specifications
   * for new attribute. The default values are located on the last
   * representation
   */

  if (heap_attrinfo_recache_attrepr (attr_info, true) != NO_ERROR
      || db_value_domain_init (&value->dbvalue, value->read_attrepr->type, value->read_attrepr->domain->precision,
                   value->read_attrepr->domain->scale) != NO_ERROR)
    {
      attr_info->num_values--;
      value->attrid = -1;
      goto exit_on_error;
    }

end:

  return ret;

exit_on_error:

  assert (ret != NO_ERROR);
  if (ret == NO_ERROR)
    {
      assert (er_errid () != NO_ERROR);
      ret = er_errid ();
      if (ret == NO_ERROR)
    {
      ret = ER_FAILED;
    }
    }
  goto end;
}
#endif

/*
 * heap_attrinfo_recache_attrepr () - Recache attribute information for given attrinfo for
 *                     each attribute value
 *   return: NO_ERROR
 *   attr_info(in/out): The attribute information structure
 *   islast_reset(in): Are we resetting information for last representation.
 *
 * Note: Recache the attribute information for given representation
 * identifier of the class in attr_info for each attribute value.
 * That is, set each attribute information to point to disk
 * related attribute information for given representation
 * identifier.
 * When we are resetting information for last representation,
 * attribute values are also initialized.
 */

static int
heap_attrinfo_recache_attrepr (HEAP_CACHE_ATTRINFO * attr_info, bool islast_reset)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int num_found_attrs;      /* Num of found attributes */
  int srch_num_attrs;       /* Num of attributes that can be searched */
  int srch_num_shared;      /* Num of shared attrs that can be searched */
  int srch_num_class;       /* Num of class attrs that can be searched */
  OR_ATTRIBUTE *search_attrepr; /* Information for disk attribute */
  int i, curr_attr;
  bool isattr_found;
  int ret = NO_ERROR;

  /* 
   * Initialize the value domain for dbvalues of all desired attributes
   */
  if (islast_reset == true)
    {
      srch_num_attrs = attr_info->last_classrepr->n_attributes;
    }
  else
    {
      srch_num_attrs = attr_info->read_classrepr->n_attributes;
    }

  /* shared and class attributes must always use the latest representation */
  srch_num_shared = attr_info->last_classrepr->n_shared_attrs;
  srch_num_class = attr_info->last_classrepr->n_class_attrs;

  for (num_found_attrs = 0, curr_attr = 0; curr_attr < attr_info->num_values; curr_attr++)
    {
      /* 
       * Go over the list of attributes (instance, shared, and class attrs)
       * until the desired attribute is found
       */
      isattr_found = false;
      if (islast_reset == true)
    {
      search_attrepr = attr_info->last_classrepr->attributes;
    }
      else
    {
      search_attrepr = attr_info->read_classrepr->attributes;
    }

      value = &attr_info->values[curr_attr];

      if (value->attrid == -1)
    {
      /* Case that we want all attributes */
      value->attrid = search_attrepr[curr_attr].id;
    }

      for (i = 0; isattr_found == false && i < srch_num_attrs; i++, search_attrepr++)
    {
      /* 
       * Is this a desired instance attribute?
       */
      if (value->attrid == search_attrepr->id)
        {
          /* 
           * Found it.
           * Initialize the attribute value information
           */
          isattr_found = true;
          value->attr_type = HEAP_INSTANCE_ATTR;
          if (islast_reset == true)
        {
          value->last_attrepr = search_attrepr;
          /* 
           * The server does not work with DB_TYPE_OBJECT but DB_TYPE_OID
           */
          if (value->last_attrepr->type == DB_TYPE_OBJECT)
            {
              value->last_attrepr->type = DB_TYPE_OID;
            }

          if (value->state == HEAP_UNINIT_ATTRVALUE)
            {
              db_value_domain_init (&value->dbvalue, value->last_attrepr->type,
                        value->last_attrepr->domain->precision, value->last_attrepr->domain->scale);
            }
        }
          else
        {
          value->read_attrepr = search_attrepr;
          /* 
           * The server does not work with DB_TYPE_OBJECT but DB_TYPE_OID
           */
          if (value->read_attrepr->type == DB_TYPE_OBJECT)
            {
              value->read_attrepr->type = DB_TYPE_OID;
            }
        }

          num_found_attrs++;
        }
    }

      /* 
       * if the desired attribute was not found in the instance attributes,
       * look for it in the shared attributes.  We always use the last_repr
       * for shared attributes.
       */

      for (i = 0, search_attrepr = attr_info->last_classrepr->shared_attrs;
       isattr_found == false && i < srch_num_shared; i++, search_attrepr++)
    {
      /* 
       * Is this a desired shared attribute?
       */
      if (value->attrid == search_attrepr->id)
        {
          /* 
           * Found it.
           * Initialize the attribute value information
           */
          isattr_found = true;
          value->attr_type = HEAP_SHARED_ATTR;
          value->last_attrepr = search_attrepr;
          /* 
           * The server does not work with DB_TYPE_OBJECT but DB_TYPE_OID
           */
          if (value->last_attrepr->type == DB_TYPE_OBJECT)
        {
          value->last_attrepr->type = DB_TYPE_OID;
        }

          if (value->state == HEAP_UNINIT_ATTRVALUE)
        {
          db_value_domain_init (&value->dbvalue, value->last_attrepr->type,
                    value->last_attrepr->domain->precision, value->last_attrepr->domain->scale);
        }
          num_found_attrs++;
        }
    }

      /* 
       * if the desired attribute was not found in the instance/shared atttrs,
       * look for it in the class attributes.  We always use the last_repr
       * for class attributes.
       */

      for (i = 0, search_attrepr = attr_info->last_classrepr->class_attrs; isattr_found == false && i < srch_num_class;
       i++, search_attrepr++)
    {
      /* 
       * Is this a desired class attribute?
       */

      if (value->attrid == search_attrepr->id)
        {
          /* 
           * Found it.
           * Initialize the attribute value information
           */
          isattr_found = true;
          value->attr_type = HEAP_CLASS_ATTR;
          if (islast_reset == true)
        {
          value->last_attrepr = search_attrepr;
        }
          else
        {
          value->read_attrepr = search_attrepr;
        }
          /* 
           * The server does not work with DB_TYPE_OBJECT but DB_TYPE_OID
           */
          if (value->last_attrepr->type == DB_TYPE_OBJECT)
        {
          value->last_attrepr->type = DB_TYPE_OID;
        }

          if (value->state == HEAP_UNINIT_ATTRVALUE)
        {
          db_value_domain_init (&value->dbvalue, value->last_attrepr->type,
                    value->last_attrepr->domain->precision, value->last_attrepr->domain->scale);
        }
          num_found_attrs++;
        }
    }
    }

  if (num_found_attrs != attr_info->num_values && islast_reset == true)
    {
      ret = ER_HEAP_UNKNOWN_ATTRS;
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ret, 1, attr_info->num_values - num_found_attrs);
      goto exit_on_error;
    }

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_attrinfo_recache () - Recache attribute information for given attrinfo
 *   return: NO_ERROR
 *   reprid(in): Cache this class representation
 *   attr_info(in/out): The attribute information structure
 *
 * Note: Recache the attribute information for given representation
 * identifier of the class in attr_info. That is, set each
 * attribute information to point to disk related attribute
 * information for given representation identifier.
 */
static int
heap_attrinfo_recache (THREAD_ENTRY * thread_p, REPR_ID reprid, HEAP_CACHE_ATTRINFO * attr_info)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int i;
  int ret = NO_ERROR;

  /* 
   * If we do not need to cache anything (case of only clear values and
   * disk repr structure).. return
   */

  if (attr_info->read_classrepr != NULL)
    {
      if (attr_info->read_classrepr->id == reprid)
    {
      return NO_ERROR;
    }

      /* 
       * Do we need to free the current cached disk representation ?
       */
      if (attr_info->read_classrepr != attr_info->last_classrepr)
    {
      heap_classrepr_free_and_init (attr_info->read_classrepr, &attr_info->read_cacheindex);
    }
      attr_info->read_classrepr = NULL;
    }

  if (reprid == NULL_REPRID)
    {
      return NO_ERROR;
    }

  if (reprid == attr_info->last_classrepr->id)
    {
      /* 
       * Take a short cut
       */
      if (attr_info->values != NULL)
    {
      for (i = 0; i < attr_info->num_values; i++)
        {
          value = &attr_info->values[i];
          value->read_attrepr = value->last_attrepr;
        }
    }
      attr_info->read_classrepr = attr_info->last_classrepr;
      attr_info->read_cacheindex = -1;  /* Don't need to free this one */
      return NO_ERROR;
    }

  /* 
   * Cache the desired class representation information
   */
  if (attr_info->values != NULL)
    {
      for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      value->read_attrepr = NULL;
    }
    }
  attr_info->read_classrepr =
    heap_classrepr_get (thread_p, &attr_info->class_oid, NULL, reprid, &attr_info->read_cacheindex);
  if (attr_info->read_classrepr == NULL)
    {
      goto exit_on_error;
    }

  if (heap_attrinfo_recache_attrepr (attr_info, false) != NO_ERROR)
    {
      heap_classrepr_free_and_init (attr_info->read_classrepr, &attr_info->read_cacheindex);

      goto exit_on_error;
    }

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_attrinfo_end () - Done with attribute information structure
 *   return: void
 *   attr_info(in/out): The attribute information structure
 *
 * Note: Release any memory allocated for attribute information related
 * reading of instances.
 */
void
heap_attrinfo_end (THREAD_ENTRY * thread_p, HEAP_CACHE_ATTRINFO * attr_info)
{
  int ret = NO_ERROR;

  /* check to make sure the attr_info has been used */
  if (attr_info->num_values == -1)
    {
      return;
    }

  /* 
   * Free any attribute and class representation information
   */
  ret = heap_attrinfo_clear_dbvalues (attr_info);
  ret = heap_attrinfo_recache (thread_p, NULL_REPRID, attr_info);

  if (attr_info->last_classrepr != NULL)
    {
      heap_classrepr_free_and_init (attr_info->last_classrepr, &attr_info->last_cacheindex);
    }

  if (attr_info->values)
    {
      db_private_free_and_init (thread_p, attr_info->values);
    }
  OID_SET_NULL (&attr_info->class_oid);

  /* 
   * Bash this so that we ensure that heap_attrinfo_end is idempotent.
   */
  attr_info->num_values = -1;

}

/*
 * heap_attrinfo_clear_dbvalues () - Clear current dbvalues of attribute
 *                                 information
 *   return: NO_ERROR
 *   attr_info(in/out): The attribute information structure
 *
 * Note: Clear any current dbvalues associated with attribute information.
 */
int
heap_attrinfo_clear_dbvalues (HEAP_CACHE_ATTRINFO * attr_info)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  OR_ATTRIBUTE *attrepr;    /* Which one current repr of default one */
  int i;
  int ret = NO_ERROR;

  /* check to make sure the attr_info has been used */
  if (attr_info->num_values == -1)
    {
      return NO_ERROR;
    }

  if (attr_info->values != NULL)
    {
      for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      if (value->state != HEAP_UNINIT_ATTRVALUE)
        {
          /* 
           * Was the value set up from a default value or from a representation
           * of the object
           */
          attrepr = ((value->read_attrepr != NULL) ? value->read_attrepr : value->last_attrepr);
          if (attrepr != NULL)
        {
          if (pr_clear_value (&value->dbvalue) != NO_ERROR)
            {
              ret = ER_FAILED;
            }
          value->state = HEAP_UNINIT_ATTRVALUE;
        }
        }
    }
    }
  OID_SET_NULL (&attr_info->inst_oid);
  attr_info->inst_chn = NULL_CHN;

  return ret;
}

/*
 * heap_attrvalue_read () - Read attribute information of given attribute cache
 *                        and instance
 *   return: NO_ERROR
 *   recdes(in): Instance record descriptor
 *   value(in): Disk value attribute information
 *   attr_info(in/out): The attribute information structure
 *
 * Note: Read the dbvalue of the given value attribute information.
 */
static int
heap_attrvalue_read (RECDES * recdes, HEAP_ATTRVALUE * value, HEAP_CACHE_ATTRINFO * attr_info)
{
  OR_BUF buf;
  PR_TYPE *pr_type;     /* Primitive type array function structure */
  OR_ATTRIBUTE *volatile attrepr;
  char *disk_data = NULL;
  int disk_bound = false;
  volatile int disk_length = -1;
  int ret = NO_ERROR;

  /* Initialize disk value information */
  disk_data = NULL;
  disk_bound = false;
  disk_length = -1;

  /* 
   * Does attribute exist in this disk representation?
   */

  if (recdes == NULL || recdes->data == NULL || value->read_attrepr == NULL || value->attr_type == HEAP_SHARED_ATTR
      || value->attr_type == HEAP_CLASS_ATTR)
    {
      /* 
       * Either the attribute is a shared or class attr, or the attribute
       * does not exist in this disk representation, or we do not have
       * the disk object (recdes), get default value if any...
       */
      attrepr = value->last_attrepr;
      disk_length = value->last_attrepr->default_value.val_length;
      if (disk_length > 0)
    {
      disk_data = (char *) value->last_attrepr->default_value.value;
      disk_bound = true;
    }
    }
  else
    {
      attrepr = value->read_attrepr;
      /* Is it a fixed size attribute ? */
      if (value->read_attrepr->is_fixed != 0)
    {
      /* 
       * A fixed attribute.
       */
      if (!OR_FIXED_ATT_IS_UNBOUND (recdes->data, attr_info->read_classrepr->n_variable,
                    attr_info->read_classrepr->fixed_length, value->read_attrepr->position))
        {
          /* 
           * The fixed attribute is bound. Access its information
           */
          disk_data =
        ((char *) recdes->data
         + OR_FIXED_ATTRIBUTES_OFFSET_BY_OBJ (recdes->data,
                              attr_info->read_classrepr->n_variable)
         + value->read_attrepr->location);
          disk_length = tp_domain_disk_size (value->read_attrepr->domain);
          disk_bound = true;
        }
    }
      else
    {
      /* 
       * A variable attribute
       */
      if (!OR_VAR_IS_NULL (recdes->data, value->read_attrepr->location))
        {
          /* 
           * The variable attribute is bound.
           * Find its location through the variable offset attribute table.
           */
          disk_data = ((char *) recdes->data + OR_VAR_OFFSET (recdes->data, value->read_attrepr->location));

          disk_bound = true;
          switch (TP_DOMAIN_TYPE (attrepr->domain))
        {
        case DB_TYPE_BLOB:
        case DB_TYPE_CLOB:
        case DB_TYPE_SET:   /* it may be just a little bit fast */
        case DB_TYPE_MULTISET:
        case DB_TYPE_SEQUENCE:
          OR_VAR_LENGTH (disk_length, recdes->data, value->read_attrepr->location,
                 attr_info->read_classrepr->n_variable);
          break;
        default:
          disk_length = -1; /* remains can read without disk_length */
        }
        }
    }
    }

  /* 
   * From now on, I should only use attrepr.. it will point to either
   * a current value or a default one
   */

  /* 
   * Clear/decache any old value
   */
  if (value->state != HEAP_UNINIT_ATTRVALUE)
    {
      (void) pr_clear_value (&value->dbvalue);
    }


  /* 
   * Now make the dbvalue according to the disk data value
   */

  if (disk_data == NULL || disk_bound == false)
    {
      /* Unbound attribute, set it to null value */
      ret = db_value_domain_init (&value->dbvalue, attrepr->type, attrepr->domain->precision, attrepr->domain->scale);
      if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }
      value->state = HEAP_READ_ATTRVALUE;
    }
  else
    {
      /* 
       * Read the value according to disk information that was found
       */
      OR_BUF_INIT2 (buf, disk_data, disk_length);
      buf.error_abort = 1;

      switch (_setjmp (buf.env))
    {
    case 0:
      /* Do not copy the string--just use the pointer.  The pr_ routines for strings and sets have different
       * semantics for length. A negative length value for strings means "don't copy the string, just use the
       * pointer". For sets, don't translate the set into memory representation at this time.  It will only be
       * translated when needed. */
      pr_type = PR_TYPE_FROM_ID (attrepr->type);
      if (pr_type)
        {
          (*(pr_type->data_readval)) (&buf, &value->dbvalue, attrepr->domain, disk_length, false, NULL, 0);
        }
      value->state = HEAP_READ_ATTRVALUE;
      break;
    default:
      /* 
       * An error was found during the reading of the attribute value
       */
      (void) db_value_domain_init (&value->dbvalue, attrepr->type, attrepr->domain->precision,
                       attrepr->domain->scale);
      value->state = HEAP_UNINIT_ATTRVALUE;
      ret = ER_FAILED;
      break;
    }
    }

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_midxkey_get_value () -
 *   return:
 *   recdes(in):
 *   att(in):
 *   value(out):
 *   attr_info(in):
 */
static int
heap_midxkey_get_value (RECDES * recdes, OR_ATTRIBUTE * att, DB_VALUE * value, HEAP_CACHE_ATTRINFO * attr_info)
{
  char *disk_data = NULL;
  bool found = true;        /* Does attribute(att) exist in this disk representation? */
  int i;

  /* Initialize disk value information */
  disk_data = NULL;
  db_make_null (value);

  if (recdes != NULL && recdes->data != NULL && att != NULL)
    {
      if (or_rep_id (recdes) != attr_info->last_classrepr->id)
    {
      found = false;
      for (i = 0; i < attr_info->read_classrepr->n_attributes; i++)
        {
          if (attr_info->read_classrepr->attributes[i].id == att->id)
        {
          att = &attr_info->read_classrepr->attributes[i];
          found = true;
          break;
        }
        }
    }

      if (found == false)
    {
      /* It means that the representation has an attribute which was created after insertion of the record. In this 
       * case, return the default value of the attribute if it exists. */
      if (att->default_value.val_length > 0)
        {
          disk_data = (char *) att->default_value.value;
        }
    }
      else
    {
      /* Is it a fixed size attribute ? */
      if (att->is_fixed != 0)
        {           /* A fixed attribute.  */
          if (!OR_FIXED_ATT_IS_UNBOUND (recdes->data, attr_info->read_classrepr->n_variable,
                        attr_info->read_classrepr->fixed_length, att->position))
        {
          /* The fixed attribute is bound. Access its information */
          disk_data =
            ((char *) recdes->data +
             OR_FIXED_ATTRIBUTES_OFFSET_BY_OBJ (recdes->data,
                            attr_info->read_classrepr->n_variable) + att->location);
        }
        }
      else
        {           /* A variable attribute */
          if (!OR_VAR_IS_NULL (recdes->data, att->location))
        {
          /* The variable attribute is bound. Find its location through the variable offset attribute table. */
          disk_data = ((char *) recdes->data + OR_VAR_OFFSET (recdes->data, att->location));
        }
        }
    }
    }
  else
    {
      assert (0);
      return ER_FAILED;
    }

  if (disk_data != NULL)
    {
      OR_BUF buf;

      or_init (&buf, disk_data, -1);
      (*(att->domain->type->data_readval)) (&buf, value, att->domain, -1, false, NULL, 0);
    }

  return NO_ERROR;
}

/*
 * heap_attrinfo_read_dbvalues () - Find db_values of desired attributes of given
 *                                instance
 *   return: NO_ERROR
 *   inst_oid(in): The instance oid
 *   recdes(in): The instance Record descriptor
 *   attr_info(in/out): The attribute information structure which describe the
 *                      desired attributes
 *
 * Note: Find DB_VALUES of desired attributes of given instance.
 * The attr_info structure must have already been initialized
 * with the desired attributes.
 *
 * If the inst_oid and the recdes are NULL, then we must be
 * reading only shared and/or class attributes which are found
 * in the last representation.
 */
int
heap_attrinfo_read_dbvalues (THREAD_ENTRY * thread_p, const OID * inst_oid, RECDES * recdes,
                 HEAP_SCANCACHE * scan_cache, HEAP_CACHE_ATTRINFO * attr_info)
{
  int i;
  REPR_ID reprid;       /* The disk representation of the object */
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int ret = NO_ERROR;

  /* check to make sure the attr_info has been used */
  if (attr_info->num_values == -1)
    {
      return NO_ERROR;
    }

  /* 
   * Make sure that we have the needed cached representation.
   */

  if (inst_oid != NULL && recdes != NULL && recdes->data != NULL)
    {
      reprid = or_rep_id (recdes);

      if (attr_info->read_classrepr == NULL || attr_info->read_classrepr->id != reprid)
    {
      /* Get the needed representation */
      ret = heap_attrinfo_recache (thread_p, reprid, attr_info);
      if (ret != NO_ERROR)
        {
          goto exit_on_error;
        }
    }
    }

  /* 
   * Go over each attribute and read it
   */

  for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      ret = heap_attrvalue_read (recdes, value, attr_info);
      if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }
    }

  /* 
   * Cache the information of the instance
   */
  if (inst_oid != NULL && recdes != NULL && recdes->data != NULL)
    {
      attr_info->inst_chn = or_chn (recdes);
      attr_info->inst_oid = *inst_oid;
    }

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

int
heap_attrinfo_read_dbvalues_without_oid (THREAD_ENTRY * thread_p, RECDES * recdes, HEAP_CACHE_ATTRINFO * attr_info)
{
  int i;
  REPR_ID reprid;       /* The disk representation of the object */
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int ret = NO_ERROR;

  /* check to make sure the attr_info has been used */
  if (attr_info->num_values == -1)
    {
      return NO_ERROR;
    }

  /* 
   * Make sure that we have the needed cached representation.
   */

  if (recdes != NULL)
    {
      reprid = or_rep_id (recdes);

      if (attr_info->read_classrepr == NULL || attr_info->read_classrepr->id != reprid)
    {
      /* Get the needed representation */
      ret = heap_attrinfo_recache (thread_p, reprid, attr_info);
      if (ret != NO_ERROR)
        {
          goto exit_on_error;
        }
    }
    }

  /* 
   * Go over each attribute and read it
   */

  for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      ret = heap_attrvalue_read (recdes, value, attr_info);
      if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }
    }

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}


/*
 * heap_attrinfo_delete_lob ()
 *   return: NO_ERROR
 *   thread_p(in):
 *   recdes(in): The instance Record descriptor
 *   attr_info(in): The attribute information structure which describe the
 *                  desired attributes
 *
 */
int
heap_attrinfo_delete_lob (THREAD_ENTRY * thread_p, RECDES * recdes, HEAP_CACHE_ATTRINFO * attr_info)
{
  int i;
  HEAP_ATTRVALUE *value;
  int ret = NO_ERROR;

  assert (attr_info != NULL);
  assert (attr_info->num_values > 0);

  /* 
   * Make sure that we have the needed cached representation.
   */

  if (recdes != NULL)
    {
      REPR_ID reprid;
      reprid = or_rep_id (recdes);
      if (attr_info->read_classrepr == NULL || attr_info->read_classrepr->id != reprid)
    {
      /* Get the needed representation */
      ret = heap_attrinfo_recache (thread_p, reprid, attr_info);
      if (ret != NO_ERROR)
        {
          goto exit_on_error;
        }
    }
    }

  /* 
   * Go over each attribute and delete the data if it's lob type
   */

  for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      if (value->last_attrepr->type == DB_TYPE_BLOB || value->last_attrepr->type == DB_TYPE_CLOB)
    {
      if (value->state == HEAP_UNINIT_ATTRVALUE && recdes != NULL)
        {
          ret = heap_attrvalue_read (recdes, value, attr_info);
          if (ret != NO_ERROR)
        {
          goto exit_on_error;
        }
        }
      if (!db_value_is_null (&value->dbvalue))
        {
          DB_ELO *elo;
          assert (db_value_type (&value->dbvalue) == DB_TYPE_BLOB
              || db_value_type (&value->dbvalue) == DB_TYPE_CLOB);
          elo = db_get_elo (&value->dbvalue);
          if (elo)
        {
          ret = db_elo_delete (elo);
        }
          value->state = HEAP_WRITTEN_ATTRVALUE;
        }
    }
    }

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_attrinfo_dump () - Dump value of attribute information
 *   return:
 *   attr_info(in): The attribute information structure
 *   dump_schema(in):
 *
 * Note: Dump attribute value of given attribute information.
 */
void
heap_attrinfo_dump (THREAD_ENTRY * thread_p, FILE * fp, HEAP_CACHE_ATTRINFO * attr_info, bool dump_schema)
{
  int i;
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int ret = NO_ERROR;

  /* check to make sure the attr_info has been used */
  if (attr_info->num_values == -1)
    {
      fprintf (fp, "  Empty attrinfo\n");
      return;
    }

  /* 
   * Dump attribute schema information
   */

  if (dump_schema == true)
    {
      ret = heap_classrepr_dump (thread_p, fp, &attr_info->class_oid, attr_info->read_classrepr);
    }

  for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      fprintf (fp, "  Attrid = %d, state = %d, type = %s\n", value->attrid, value->state,
           pr_type_name (value->read_attrepr->type));
      /* 
       * Dump the value in memory format
       */

      fprintf (fp, "  Memory_value_format:\n");
      fprintf (fp, "    value = ");
      db_value_fprint (fp, &value->dbvalue);
      fprintf (fp, "\n\n");
    }

}

/*
 * heap_attrvalue_locate () - Locate disk attribute value information
 *   return: attrvalue or NULL
 *   attrid(in): The desired attribute identifier
 *   attr_info(in/out): The attribute information structure which describe the
 *                      desired attributes
 *
 * Note: Locate the disk attribute value information of an attribute
 * information structure which have been already initialized.
 */
HEAP_ATTRVALUE *
heap_attrvalue_locate (ATTR_ID attrid, HEAP_CACHE_ATTRINFO * attr_info)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int i;

  for (i = 0, value = attr_info->values; i < attr_info->num_values; i++, value++)
    {
      if (attrid == value->attrid)
    {
      return value;
    }
    }

  return NULL;
}

/*
 * heap_locate_attribute () -
 *   return:
 *   attrid(in):
 *   attr_info(in):
 */
static OR_ATTRIBUTE *
heap_locate_attribute (ATTR_ID attrid, HEAP_CACHE_ATTRINFO * attr_info)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int i;

  for (i = 0, value = attr_info->values; i < attr_info->num_values; i++, value++)
    {
      if (attrid == value->attrid)
    {
      /* Some altered attributes might have only the last representations of them. */
      return (value->read_attrepr != NULL) ? value->read_attrepr : value->last_attrepr;
    }
    }

  return NULL;
}

/*
 * heap_locate_last_attrepr () -
 *   return:
 *   attrid(in):
 *   attr_info(in):
 */
OR_ATTRIBUTE *
heap_locate_last_attrepr (ATTR_ID attrid, HEAP_CACHE_ATTRINFO * attr_info)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int i;

  for (i = 0, value = attr_info->values; i < attr_info->num_values; i++, value++)
    {
      if (attrid == value->attrid)
    {
      return value->last_attrepr;
    }
    }

  return NULL;
}

/*
 * heap_attrinfo_access () - Access an attribute value which has been already read
 *   return:
 *   attrid(in): The desired attribute identifier
 *   attr_info(in/out): The attribute information structure which describe the
 *                      desired attributes
 *
 * Note: Find DB_VALUE of desired attribute identifier.
 * The dbvalue attributes must have been read by now using the
 * function heap_attrinfo_read_dbvalues ()
 */
DB_VALUE *
heap_attrinfo_access (ATTR_ID attrid, HEAP_CACHE_ATTRINFO * attr_info)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */

  /* check to make sure the attr_info has been used */
  if (attr_info->num_values == -1)
    {
      return NULL;
    }

  value = heap_attrvalue_locate (attrid, attr_info);
  if (value == NULL || value->state == HEAP_UNINIT_ATTRVALUE)
    {
      er_log_debug (ARG_FILE_LINE, "heap_attrinfo_access: Unknown attrid = %d", attrid);
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      return NULL;
    }

  return &value->dbvalue;
}

/*
 * heap_get_class_subclasses () - get OIDs of subclasses for a given class
 * return : error code or NO_ERROR
 * thread_p (in)  :
 * class_oid (in) : OID of the parent class
 * count (out)    : size of the subclasses array
 * subclasses (out) : array containing OIDs of subclasses
 *
 * Note: The subclasses array is maintained as an array of OID's,
 *   the last element in the array will satisfy the OID_ISNULL() test.
 *   The array_size has the number of actual elements allocated in the
 *   array which may be more than the number of slots that have non-NULL
 *   OIDs. The function adds the subclass oids to the existing array.
 *   If the array is not large enough, it is reallocated using realloc.
 */
int
heap_get_class_subclasses (THREAD_ENTRY * thread_p, const OID * class_oid, int *count, OID ** subclasses)
{
  HEAP_SCANCACHE scan_cache;
  RECDES recdes;
  int error = NO_ERROR;

  error = heap_scancache_quick_start_root_hfid (thread_p, &scan_cache);
  if (error != NO_ERROR)
    {
      return error;
    }

  if (heap_get_class_record (thread_p, class_oid, &recdes, &scan_cache, PEEK) != S_SUCCESS)
    {
      heap_scancache_end (thread_p, &scan_cache);
      return ER_FAILED;
    }

  error = orc_subclasses_from_record (&recdes, count, subclasses);

  heap_scancache_end (thread_p, &scan_cache);

  return error;
}

/*
 * heap_class_get_partition_info () - Get partition information for the class
 *                    identified by class_oid
 * return : error code or NO_ERROR
 * class_oid (in) : class_oid
 * partition_info (in/out) : partition information
 * class_hfid (in/out) : HFID of the partitioned class
 * repr_id  (in/out) : class representation id
 * has_partition_info (out):
 *
 * Note: This function extracts the partition information from a class OID.
 */
static int
heap_class_get_partition_info (THREAD_ENTRY * thread_p, const OID * class_oid, OR_PARTITION * partition_info,
                   HFID * class_hfid, REPR_ID * repr_id, int *has_partition_info)
{
  int error = NO_ERROR;
  RECDES recdes;
  HEAP_SCANCACHE scan_cache;

  assert (class_oid != NULL);

  if (heap_scancache_quick_start_root_hfid (thread_p, &scan_cache) != NO_ERROR)
    {
      return ER_FAILED;
    }

  scan_cache.mvcc_snapshot = logtb_get_mvcc_snapshot (thread_p);
  if (scan_cache.mvcc_snapshot == NULL)
    {
      error = er_errid ();
      return (error == NO_ERROR ? ER_FAILED : error);
    }

  if (heap_get_class_record (thread_p, class_oid, &recdes, &scan_cache, PEEK) != S_SUCCESS)
    {
      error = ER_FAILED;
      goto cleanup;
    }

  error = or_class_get_partition_info (&recdes, partition_info, repr_id, has_partition_info);
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  if (class_hfid != NULL)
    {
      or_class_hfid (&recdes, class_hfid);
    }

cleanup:
  heap_scancache_end (thread_p, &scan_cache);

  return error;
}

/*
 * heap_get_partition_attributes () - get attribute ids for columns of
 *                    _db_partition class
 * return : error code or NO_ERROR
 * thread_p (in)      :
 * cls_oid (in)       : _db_partition class OID
 * type_id (in/out)   : holder for the type attribute id
 * values_id (in/out) : holder for the values attribute id
 */
static int
heap_get_partition_attributes (THREAD_ENTRY * thread_p, const OID * cls_oid, ATTR_ID * type_id, ATTR_ID * values_id)
{
  RECDES recdes;
  HEAP_SCANCACHE scan;
  HEAP_CACHE_ATTRINFO attr_info;
  int error = NO_ERROR;
  int i = 0;
  char *attr_name = NULL;
  bool is_scan_cache_started = false, is_attrinfo_started = false;
  char *string = NULL;
  int alloced_string = 0;


  if (type_id == NULL || values_id == NULL)
    {
      assert (false);
      error = ER_FAILED;
      goto cleanup;
    }
  *type_id = *values_id = NULL_ATTRID;

  if (heap_scancache_quick_start_root_hfid (thread_p, &scan) != NO_ERROR)
    {
      error = ER_FAILED;
      goto cleanup;
    }
  is_scan_cache_started = true;

  error = heap_attrinfo_start (thread_p, cls_oid, -1, NULL, &attr_info);
  if (error != NO_ERROR)
    {
      goto cleanup;
    }
  is_attrinfo_started = true;

  if (heap_get_class_record (thread_p, cls_oid, &recdes, &scan, PEEK) != S_SUCCESS)
    {
      error = ER_FAILED;
      goto cleanup;
    }

  for (i = 0; i < attr_info.num_values && (*type_id == NULL_ATTRID || *values_id == NULL_ATTRID); i++)
    {
      alloced_string = 0;
      string = NULL;

      error = or_get_attrname (&recdes, i, &string, &alloced_string);
      if (error != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto cleanup;
    }

      attr_name = string;
      if (attr_name == NULL)
    {
      error = ER_FAILED;
      goto cleanup;
    }
      if (strcmp (attr_name, "ptype") == 0)
    {
      *type_id = i;
    }

      if (strcmp (attr_name, "pvalues") == 0)
    {
      *values_id = i;
    }

      if (string != NULL && alloced_string == 1)
    {
      db_private_free_and_init (thread_p, string);
    }
    }

  if (*type_id == NULL_ATTRID || *values_id == NULL_ATTRID)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      error = ER_FAILED;
    }

cleanup:
  if (is_attrinfo_started)
    {
      heap_attrinfo_end (thread_p, &attr_info);
    }
  if (is_scan_cache_started)
    {
      heap_scancache_end (thread_p, &scan);
    }
  return error;
}

/*
 * heap_get_partitions_from_subclasses () - Get partition information from a
 *                      list of subclasses
 * return : error code or NO_ERROR
 * thread_p (in)    :
 * subclasses (in)  : subclasses OIDs
 * parts_count (in/out) : number of "useful" elements in parts
 * parts (in/out)   : partitions
 *
 *  Note: Memory for the partition array must be allocated before calling this
 *  function and must be enough to store all partitions. The value from
 *  position 0 in the partitions array will contain information from the
 *  master class
 */
static int
heap_get_partitions_from_subclasses (THREAD_ENTRY * thread_p, const OID * subclasses, int *parts_count,
                     OR_PARTITION * parts)
{
  int part_idx = 0, i;
  int error = NO_ERROR;
  HFID part_hfid;
  REPR_ID repr_id;
  int has_partition_info = 0;

  if (parts == NULL)
    {
      assert (false);
      error = ER_FAILED;
      goto cleanup;
    }

  /* the partition information for the master class will be set by the caller */
  part_idx = 1;

  /* loop through subclasses and load partition information if the subclass is a partition */
  for (i = 0; !OID_ISNULL (&subclasses[i]); i++)
    {
      /* Get partition information from this subclass. part_info will be the OID of the tuple from _db_partition
       * containing partition information */
      error =
    heap_class_get_partition_info (thread_p, &subclasses[i], &parts[part_idx], &part_hfid, &repr_id,
                       &has_partition_info);
      if (error != NO_ERROR)
    {
      goto cleanup;
    }

      if (has_partition_info == 0)
    {
      /* this is not a partition, this is a simple subclass */
      continue;
    }

      COPY_OID (&(parts[part_idx].class_oid), &subclasses[i]);
      HFID_COPY (&(parts[part_idx].class_hfid), &part_hfid);
      parts[part_idx].rep_id = repr_id;

      part_idx++;
    }
  *parts_count = part_idx;

cleanup:
  if (error != NO_ERROR)
    {
      /* free memory for the values of partitions */
      for (i = 1; i < part_idx; i++)
    {
      if (parts[i].values != NULL)
        {
          db_seq_free (parts[i].values);
        }
    }
    }
  return error;
}

/*
 * heap_get_class_partitions () - get partitions information for a class
 * return : error code or NO_ERROR
 * thread_p (in)    :
 * class_oid (in)   : class OID
 * parts (in/out)   : partitions information
 * parts_count (in/out) : number of partitions
 */
int
heap_get_class_partitions (THREAD_ENTRY * thread_p, const OID * class_oid, OR_PARTITION ** parts, int *parts_count)
{
  int subclasses_count = 0;
  OID *subclasses = NULL;
  OR_PARTITION part_info;
  int error = NO_ERROR;
  OR_PARTITION *partitions = NULL;
  REPR_ID class_repr_id = NULL_REPRID;
  HFID class_hfid;
  int has_partition_info = 0;

  *parts = NULL;
  *parts_count = 0;
  part_info.values = NULL;

  /* This class might have partitions and subclasses. In order to get partition information we have to: 1. Get the OIDs 
   * for all subclasses 2. Get partition information for all OIDs 3. Build information only for those subclasses which
   * are partitions */
  error =
    heap_class_get_partition_info (thread_p, class_oid, &part_info, &class_hfid, &class_repr_id, &has_partition_info);
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  if (has_partition_info == 0)
    {
      /* this class does not have partitions */
      error = NO_ERROR;
      goto cleanup;
    }

  /* Get OIDs for subclasses of class_oid. Some of them will be partitions */
  error = heap_get_class_subclasses (thread_p, class_oid, &subclasses_count, &subclasses);
  if (error != NO_ERROR)
    {
      goto cleanup;
    }
  else if (subclasses_count == 0)
    {
      /* This means that class_oid actually points to a partition and not the master class. We return NO_ERROR here
       * since there's no partition information */
      error = NO_ERROR;
      goto cleanup;
    }

  /* Allocate memory for partitions. We allocate more memory than needed here because the call to
   * heap_get_class_subclasses from above actually returned a larger count than the useful information. Also, not all
   * subclasses are necessarily partitions. */
  partitions = (OR_PARTITION *) db_private_alloc (thread_p, (subclasses_count + 1) * sizeof (OR_PARTITION));
  if (partitions == NULL)
    {
      error = ER_OUT_OF_VIRTUAL_MEMORY;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, error, 1, (subclasses_count + 1) * sizeof (OR_PARTITION));
      goto cleanup;
    }

  error = heap_get_partitions_from_subclasses (thread_p, subclasses, parts_count, partitions);
  if (error != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto cleanup;
    }

  /* fill the information for the root (partitioned class) */
  COPY_OID (&partitions[0].class_oid, class_oid);
  HFID_COPY (&partitions[0].class_hfid, &class_hfid);
  partitions[0].partition_type = part_info.partition_type;
  partitions[0].rep_id = class_repr_id;
  partitions[0].values = NULL;
  if (part_info.values != NULL)
    {
      partitions[0].values = set_copy (part_info.values);
      if (partitions[0].values == NULL)
    {
      error = er_errid ();
      goto cleanup;
    }
      set_free (part_info.values);
      part_info.values = NULL;
    }

  *parts = partitions;

cleanup:
  if (subclasses != NULL)
    {
      free_and_init (subclasses);
    }
  if (part_info.values != NULL)
    {
      set_free (part_info.values);
    }
  if (error != NO_ERROR && partitions != NULL)
    {
      db_private_free (thread_p, partitions);
      *parts = NULL;
      *parts_count = 0;
    }
  return error;
}

/*
 * heap_clear_partition_info () - free partitions info from heap_get_class_partitions
 * return : void
 * thread_p (in)    :
 * parts (in)       : partitions information
 * parts_count (in) : number of partitions
 */
void
heap_clear_partition_info (THREAD_ENTRY * thread_p, OR_PARTITION * parts, int parts_count)
{
  if (parts != NULL)
    {
      int i;

      for (i = 0; i < parts_count; i++)
    {
      if (parts[i].values != NULL)
        {
          db_seq_free (parts[i].values);
        }
    }

      db_private_free (thread_p, parts);
    }
}

/*
 * heap_get_class_supers () - get OIDs of superclasses of a class
 * return : error code or NO_ERROR
 * thread_p (in)  : thread entry
 * class_oid (in) : OID of the subclass
 * super_oids (in/out) : OIDs of the superclasses
 * count (in/out)      : number of elements in super_oids
 */
int
heap_get_class_supers (THREAD_ENTRY * thread_p, const OID * class_oid, OID ** super_oids, int *count)
{
  HEAP_SCANCACHE scan_cache;
  RECDES recdes;
  int error = NO_ERROR;

  error = heap_scancache_quick_start_root_hfid (thread_p, &scan_cache);
  if (error != NO_ERROR)
    {
      return error;
    }

  if (heap_get_class_record (thread_p, class_oid, &recdes, &scan_cache, PEEK) != S_SUCCESS)
    {
      heap_scancache_end (thread_p, &scan_cache);
      return ER_FAILED;
    }

  error = orc_superclasses_from_record (&recdes, count, super_oids);

  heap_scancache_end (thread_p, &scan_cache);

  return error;
}

/*
 * heap_attrinfo_check () -
 *   return: NO_ERROR
 *   inst_oid(in): The instance oid
 *   attr_info(in): The attribute information structure which describe the
 *                  desired attributes
 */
static int
heap_attrinfo_check (const OID * inst_oid, HEAP_CACHE_ATTRINFO * attr_info)
{
  int ret = NO_ERROR;

  if (inst_oid != NULL)
    {
      /* 
       * The OIDs must be equal
       */
      if (!OID_EQ (&attr_info->inst_oid, inst_oid))
    {
      if (!OID_ISNULL (&attr_info->inst_oid))
        {
          ret = ER_HEAP_WRONG_ATTRINFO;
          er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ret, 6, attr_info->inst_oid.volid,
              attr_info->inst_oid.pageid, attr_info->inst_oid.slotid, inst_oid->volid, inst_oid->pageid,
              inst_oid->slotid);
          goto exit_on_error;
        }

      attr_info->inst_oid = *inst_oid;
    }
    }
  else
    {
      if (!OID_ISNULL (&attr_info->inst_oid))
    {
      ret = ER_HEAP_WRONG_ATTRINFO;
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ret, 6, attr_info->inst_oid.volid, attr_info->inst_oid.pageid,
          attr_info->inst_oid.slotid, NULL_VOLID, NULL_PAGEID, NULL_SLOTID);
      goto exit_on_error;
    }
    }

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_attrinfo_set () - Set the value of given attribute
 *   return: NO_ERROR
 *   inst_oid(in): The instance oid
 *   attrid(in): The identifier of the attribute to be set
 *   attr_val(in): The memory value of the attribute
 *   attr_info(in/out): The attribute information structure which describe the
 *                      desired attributes
 *
 * Note: Set DB_VALUE of desired attribute identifier.
 */
int
heap_attrinfo_set (const OID * inst_oid, ATTR_ID attrid, DB_VALUE * attr_val, HEAP_CACHE_ATTRINFO * attr_info)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  PR_TYPE *pr_type;     /* Primitive type array function structure */
  TP_DOMAIN_STATUS dom_status;
  int ret = NO_ERROR;

  /* 
   * check to make sure the attr_info has been used, should never be empty.
   */

  if (attr_info->num_values == -1)
    {
      return ER_FAILED;
    }

  ret = heap_attrinfo_check (inst_oid, attr_info);
  if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }

  value = heap_attrvalue_locate (attrid, attr_info);
  if (value == NULL)
    {
      goto exit_on_error;
    }

  pr_type = PR_TYPE_FROM_ID (value->last_attrepr->type);
  if (pr_type == NULL)
    {
      goto exit_on_error;
    }

  ret = pr_clear_value (&value->dbvalue);
  if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }

  ret =
    db_value_domain_init (&value->dbvalue, value->last_attrepr->type, value->last_attrepr->domain->precision,
              value->last_attrepr->domain->scale);
  if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }

  /* 
   * As we use "writeval" to do the writing and that function gets
   * enough domain information, we can use non-exact domain matching
   * here to defer the coercion until it is written.
   */
  dom_status = tp_domain_check (value->last_attrepr->domain, attr_val, TP_EXACT_MATCH);
  if (dom_status == DOMAIN_COMPATIBLE)
    {
      /* 
       * the domains match exactly, set the value and proceed.  Copy
       * the source only if it's a set-valued thing (that's the purpose
       * of the third argument).
       */
      ret = (*(pr_type->setval)) (&value->dbvalue, attr_val, TP_IS_SET_TYPE (pr_type->id));
    }
  else
    {
      /* the domains don't match, must attempt coercion */
      dom_status = tp_value_auto_cast (attr_val, &value->dbvalue, value->last_attrepr->domain);
      if (dom_status != DOMAIN_COMPATIBLE)
    {
      ret = tp_domain_status_er_set (dom_status, ARG_FILE_LINE, attr_val, value->last_attrepr->domain);
      assert (er_errid () != NO_ERROR);

      db_make_null (&value->dbvalue);
    }
    }

  if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }

  value->state = HEAP_WRITTEN_ATTRVALUE;

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_attrinfo_set_uninitialized () - Read unitialized attributes
 *   return: NO_ERROR
 *   inst_oid(in): The instance oid
 *   recdes(in): The instance record descriptor
 *   attr_info(in/out): The attribute information structure which describe the
 *                      desired attributes
 *
 * Note: Read the db values of the unitialized attributes from the
 * given recdes. This function is used when we are ready to
 * transform an object that has been updated/inserted in the server.
 * If the object has been updated, recdes must be the old object
 * (the one on disk), so we can set the rest of the uninitialized
 * attributes from the old object.
 * If the object is a new one, recdes should be NULL, since there
 * is not an object on disk, the rest of the unitialized
 * attributes are set from default values.
 */
static int
heap_attrinfo_set_uninitialized (THREAD_ENTRY * thread_p, OID * inst_oid, RECDES * recdes,
                 HEAP_CACHE_ATTRINFO * attr_info)
{
  int i;
  REPR_ID reprid;       /* Representation of object */
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int ret = NO_ERROR;

  ret = heap_attrinfo_check (inst_oid, attr_info);
  if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }

  /* 
   * Make sure that we have the needed cached representation.
   */

  if (recdes != NULL)
    {
      reprid = or_rep_id (recdes);
    }
  else
    {
      reprid = attr_info->last_classrepr->id;
    }

  if (attr_info->read_classrepr == NULL || attr_info->read_classrepr->id != reprid)
    {
      /* Get the needed representation */
      ret = heap_attrinfo_recache (thread_p, reprid, attr_info);
      if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }
    }

  /* 
   * Go over the attribute values and set the ones that have not been
   * initialized
   */
  for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      if (value->state == HEAP_UNINIT_ATTRVALUE)
    {
      ret = heap_attrvalue_read (recdes, value, attr_info);
      if (ret != NO_ERROR)
        {
          goto exit_on_error;
        }
    }
      else if (value->state == HEAP_WRITTEN_ATTRVALUE
           && (value->last_attrepr->type == DB_TYPE_BLOB || value->last_attrepr->type == DB_TYPE_CLOB))
    {
      DB_VALUE *save;
      save = db_value_copy (&value->dbvalue);
      pr_clear_value (&value->dbvalue);

      /* read and delete old value */
      ret = heap_attrvalue_read (recdes, value, attr_info);
      if (ret != NO_ERROR)
        {
          goto exit_on_error;
        }
      if (!db_value_is_null (&value->dbvalue))
        {
          DB_ELO *elo;

          assert (db_value_type (&value->dbvalue) == DB_TYPE_BLOB
              || db_value_type (&value->dbvalue) == DB_TYPE_CLOB);
          elo = db_get_elo (&value->dbvalue);
          if (elo)
        {
          ret = db_elo_delete (elo);
        }
          pr_clear_value (&value->dbvalue);
          ret = (ret >= 0 ? NO_ERROR : ret);
          if (ret != NO_ERROR)
        {
          goto exit_on_error;
        }
        }
      value->state = HEAP_WRITTEN_ATTRVALUE;
      pr_clone_value (save, &value->dbvalue);
      pr_free_ext_value (save);
    }
    }

  if (recdes != NULL)
    {
      attr_info->inst_chn = or_chn (recdes);
    }
  else
    {
      attr_info->inst_chn = -1;
    }

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_attrinfo_get_disksize () - Find the disk size needed to transform the object
 *                        represented by attr_info
 *   return: size of the object
 *   attr_info(in/out): The attribute information structure
 *   is_mvcc_class(in): true, if MVCC class
 *   offset_size_ptr(out): offset size
 *
 * Note: Find the disk size needed to transform the object represented
 * by the attribute information structure.
 */
static int
heap_attrinfo_get_disksize (HEAP_CACHE_ATTRINFO * attr_info, bool is_mvcc_class, int *offset_size_ptr)
{
  int i, size;
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */

  *offset_size_ptr = OR_BYTE_SIZE;

re_check:
  size = 0;
  for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];

      if (value->last_attrepr->is_fixed != 0)
    {
      size += tp_domain_disk_size (value->last_attrepr->domain);
    }
      else
    {
      size += pr_data_writeval_disk_size (&value->dbvalue);
    }
    }

  if (is_mvcc_class)
    {
      size += OR_MVCC_INSERT_HEADER_SIZE;
    }
  else
    {
      size += OR_NON_MVCC_HEADER_SIZE;
    }

  size += OR_VAR_TABLE_SIZE_INTERNAL (attr_info->last_classrepr->n_variable, *offset_size_ptr);
  size += OR_BOUND_BIT_BYTES (attr_info->last_classrepr->n_attributes - attr_info->last_classrepr->n_variable);

  if (*offset_size_ptr == OR_BYTE_SIZE && size > OR_MAX_BYTE)
    {
      *offset_size_ptr = OR_SHORT_SIZE; /* 2byte */
      goto re_check;
    }
  if (*offset_size_ptr == OR_SHORT_SIZE && size > OR_MAX_SHORT)
    {
      *offset_size_ptr = BIG_VAR_OFFSET_SIZE;   /* 4byte */
      goto re_check;
    }

  return size;
}

/*
 * heap_attrinfo_transform_to_disk () - Transform to disk an attribute information
 *                               kind of instance
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_DOESNT_FIT,
 *                      S_ERROR)
 *   attr_info(in/out): The attribute information structure
 *   old_recdes(in): where the object's disk format is deposited
 *   new_recdes(in):
 *
 * Note: Transform the object represented by attr_info to disk format
 */
SCAN_CODE
heap_attrinfo_transform_to_disk (THREAD_ENTRY * thread_p, HEAP_CACHE_ATTRINFO * attr_info, RECDES * old_recdes,
                 RECDES * new_recdes)
{
  return heap_attrinfo_transform_to_disk_internal (thread_p, attr_info, old_recdes, new_recdes, LOB_FLAG_INCLUDE_LOB);
}

/*
 * heap_attrinfo_transform_to_disk_except_lob () -
 *                           Transform to disk an attribute information
 *                           kind of instance. Do not create lob.
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_DOESNT_FIT,
 *                      S_ERROR)
 *   attr_info(in/out): The attribute information structure
 *   old_recdes(in): where the object's disk format is deposited
 *   new_recdes(in):
 *
 * Note: Transform the object represented by attr_info to disk format
 */
SCAN_CODE
heap_attrinfo_transform_to_disk_except_lob (THREAD_ENTRY * thread_p, HEAP_CACHE_ATTRINFO * attr_info,
                        RECDES * old_recdes, RECDES * new_recdes)
{
  return heap_attrinfo_transform_to_disk_internal (thread_p, attr_info, old_recdes, new_recdes, LOB_FLAG_EXCLUDE_LOB);
}

/*
 * heap_attrinfo_transform_to_disk_internal () -
 *                         Transform to disk an attribute information
 *                         kind of instance.
 *   return: SCAN_CODE
 *           (Either of S_SUCCESS, S_DOESNT_FIT,
 *                      S_ERROR)
 *   attr_info(in/out): The attribute information structure
 *   old_recdes(in): where the object's disk format is deposited
 *   new_recdes(in):
 *   lob_create_flag(in):
 *
 * Note: Transform the object represented by attr_info to disk format
 */
static SCAN_CODE
heap_attrinfo_transform_to_disk_internal (THREAD_ENTRY * thread_p, HEAP_CACHE_ATTRINFO * attr_info, RECDES * old_recdes,
                      RECDES * new_recdes, int lob_create_flag)
{
  OR_BUF orep, *buf;
  char *ptr_bound, *ptr_varvals;
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  DB_VALUE temp_dbvalue;
  PR_TYPE *pr_type;     /* Primitive type array function structure */
  unsigned int repid_bits;
  SCAN_CODE status;
  int i;
  DB_VALUE *dbvalue = NULL;
  int expected_size, tmp;
  volatile int offset_size;
  int mvcc_wasted_space = 0, header_size;
  bool is_mvcc_class;

  /* check to make sure the attr_info has been used, it should not be empty. */
  if (attr_info->num_values == -1)
    {
      return S_ERROR;
    }

  /* 
   * Get any of the values that have not been set/read
   */
  if (heap_attrinfo_set_uninitialized (thread_p, &attr_info->inst_oid, old_recdes, attr_info) != NO_ERROR)
    {
      return S_ERROR;
    }

  /* Start transforming the dbvalues into disk values for the object */
  OR_BUF_INIT2 (orep, new_recdes->data, new_recdes->area_size);
  buf = &orep;

  is_mvcc_class = !mvcc_is_mvcc_disabled_class (&(attr_info->class_oid));
  expected_size = heap_attrinfo_get_disksize (attr_info, is_mvcc_class, &tmp);
  offset_size = tmp;

  if (is_mvcc_class)
    {
      mvcc_wasted_space = (OR_MVCC_MAX_HEADER_SIZE - OR_MVCC_INSERT_HEADER_SIZE);
      if (old_recdes != NULL)
    {
      /* Update case, reserve space for previous version LSA. */
      expected_size += OR_MVCC_PREV_VERSION_LSA_SIZE;
      mvcc_wasted_space -= OR_MVCC_PREV_VERSION_LSA_SIZE;
    }
    }

  /* reserve enough space if need to add additional MVCC header info */
  expected_size += mvcc_wasted_space;

  switch (_setjmp (buf->env))
    {
    case 0:
      status = S_SUCCESS;

      /* 
       * Store the representation of the class along with bound bit
       * flag information
       */

      repid_bits = attr_info->last_classrepr->id;
      /* 
       * Do we have fixed value attributes ?
       */
      if ((attr_info->last_classrepr->n_attributes - attr_info->last_classrepr->n_variable) != 0)
    {
      repid_bits |= OR_BOUND_BIT_FLAG;
    }

      /* offset size */
      OR_SET_VAR_OFFSET_SIZE (repid_bits, offset_size);

      /* 
       * We must increase the current value by one so that clients
       * can detect the change in object. That is, clients will need to
       * refetch the object.
       */
      attr_info->inst_chn++;
      if (is_mvcc_class)
    {
      if (old_recdes == NULL)
        {
          repid_bits |= (OR_MVCC_FLAG_VALID_INSID << OR_MVCC_FLAG_SHIFT_BITS);
          or_put_int (buf, repid_bits);
          or_put_int (buf, 0);  /* CHN */
          or_put_bigint (buf, 0);   /* MVCC insert id */
          header_size = OR_MVCC_INSERT_HEADER_SIZE;
        }
      else
        {
          LOG_LSA null_lsa = LSA_INITIALIZER;
          repid_bits |= ((OR_MVCC_FLAG_VALID_INSID | OR_MVCC_FLAG_VALID_PREV_VERSION) << OR_MVCC_FLAG_SHIFT_BITS);
          or_put_int (buf, repid_bits);
          or_put_int (buf, 0);  /* CHN */
          or_put_bigint (buf, 0);   /* MVCC insert id */

          assert ((buf->ptr + OR_MVCC_PREV_VERSION_LSA_SIZE) <= buf->endptr);
          or_put_data (buf, (char *) &null_lsa, OR_MVCC_PREV_VERSION_LSA_SIZE); /* prev version lsa */
          header_size = OR_MVCC_INSERT_HEADER_SIZE + OR_MVCC_PREV_VERSION_LSA_SIZE;
        }
    }
      else
    {
      or_put_int (buf, repid_bits);
      or_put_int (buf, attr_info->inst_chn);
      header_size = OR_NON_MVCC_HEADER_SIZE;
    }

      /* 
       * Calculate the pointer address to variable offset attribute table,
       * fixed attributes, and variable attributes
       */

      ptr_bound = OR_GET_BOUND_BITS (buf->buffer, attr_info->last_classrepr->n_variable,
                     attr_info->last_classrepr->fixed_length);

      /* 
       * Variable offset table is relative to the beginning of the buffer
       */

      ptr_varvals = (ptr_bound
             + OR_BOUND_BIT_BYTES (attr_info->last_classrepr->n_attributes
                       - attr_info->last_classrepr->n_variable));

      /* Need to make sure that the bound array is not past the allocated buffer because OR_ENABLE_BOUND_BIT() will
       * just slam the bound bit without checking the length. */

      if (ptr_varvals + mvcc_wasted_space >= buf->endptr)
    {
      new_recdes->length = -expected_size;  /* set to negative */
      return S_DOESNT_FIT;
    }

      for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      dbvalue = &value->dbvalue;
      pr_type = value->last_attrepr->domain->type;
      if (pr_type == NULL)
        {
          return S_ERROR;
        }

      /* 
       * Is this a fixed or variable attribute ?
       */
      if (value->last_attrepr->is_fixed != 0)
        {
          /* 
           * Fixed attribute
           * Write the fixed attributes values, if unbound, does not matter
           * what value is stored. We need to set the appropiate bit in the
           * bound bit array for fixed attributes. For variable attributes,
           */
          buf->ptr = (buf->buffer
              + OR_FIXED_ATTRIBUTES_OFFSET_BY_OBJ (buf->buffer, attr_info->last_classrepr->n_variable)
              + value->last_attrepr->location);

          if (value->do_increment)
        {
          if (qdata_increment_dbval (dbvalue, dbvalue, value->do_increment) != NO_ERROR)
            {
              status = S_ERROR;
              break;
            }
        }

          if (dbvalue == NULL || db_value_is_null (dbvalue) == true)
        {
          /* 
           * This is an unbound value.
           *  1) Set any value in the fixed array value table, so we can
           *     advance to next attribute.
           *  2) and set the bound bit as unbound
           */
          db_value_domain_init (&temp_dbvalue, value->last_attrepr->type,
                    value->last_attrepr->domain->precision, value->last_attrepr->domain->scale);
          dbvalue = &temp_dbvalue;
          OR_CLEAR_BOUND_BIT (ptr_bound, value->last_attrepr->position);

          /* 
           * pad the appropriate amount, writeval needs to be modified
           * to accept a domain so it can perform this padding.
           */
          or_pad (buf, tp_domain_disk_size (value->last_attrepr->domain));

        }
          else
        {
          /* 
           * Write the value.
           */
          OR_ENABLE_BOUND_BIT (ptr_bound, value->last_attrepr->position);
          (*(pr_type->data_writeval)) (buf, dbvalue);
        }
        }
      else
        {
          /* 
           * Variable attribute
           *  1) Set the offset to this value in the variable offset table
           *  2) Set the value in the variable value portion of the disk
           *     object (Only if the value is bound)
           */

          /* 
           * Write the offset onto the variable offset table and remember
           * the current pointer to the variable offset table
           */

          if (value->do_increment != 0)
        {
          status = S_ERROR;
          break;
        }

          buf->ptr = (char *) (OR_VAR_ELEMENT_PTR (buf->buffer, value->last_attrepr->location));
          /* compute the variable offsets relative to the end of the header (beginning of variable table) */
          or_put_offset_internal (buf, CAST_BUFLEN (ptr_varvals - buf->buffer - header_size), offset_size);

          if (dbvalue != NULL && db_value_is_null (dbvalue) != true)
        {
          /* 
           * Now write the value and remember the current pointer
           * to variable value array for the next element.
           */
          buf->ptr = ptr_varvals;

          if (lob_create_flag == LOB_FLAG_INCLUDE_LOB && value->state == HEAP_WRITTEN_ATTRVALUE
              && (pr_type->id == DB_TYPE_BLOB || pr_type->id == DB_TYPE_CLOB))
            {
              DB_ELO dest_elo, *elo_p;
              char *save_meta_data, *new_meta_data;
              int error;

              assert (db_value_type (dbvalue) == DB_TYPE_BLOB || db_value_type (dbvalue) == DB_TYPE_CLOB);

              elo_p = db_get_elo (dbvalue);

              if (elo_p == NULL)
            {
              continue;
            }

              if (heap_get_class_name (thread_p, &(attr_info->class_oid), &new_meta_data) != NO_ERROR
              || new_meta_data == NULL)
            {
              status = S_ERROR;
              break;
            }
              save_meta_data = elo_p->meta_data;
              elo_p->meta_data = new_meta_data;
              error = db_elo_copy (db_get_elo (dbvalue), &dest_elo);

              free_and_init (elo_p->meta_data);
              elo_p->meta_data = save_meta_data;

              /* The purpose of HEAP_WRITTEN_LOB_ATTRVALUE is to avoid reenter this branch. In the first pass,
               * this branch is entered and elo is copied. When BUFFER_OVERFLOW happens, we need avoid to copy
               * elo again. Otherwize it will generate 2 copies. */
              value->state = HEAP_WRITTEN_LOB_ATTRVALUE;

              error = (error >= 0 ? NO_ERROR : error);
              if (error == NO_ERROR)
            {
              pr_clear_value (dbvalue);
              db_make_elo (dbvalue, pr_type->id, &dest_elo);
              dbvalue->need_clear = true;
            }
              else
            {
              status = S_ERROR;
              break;
            }
            }

          (*(pr_type->data_writeval)) (buf, dbvalue);
          ptr_varvals = buf->ptr;
        }
        }
    }

      if (attr_info->last_classrepr->n_variable > 0)
    {
      /* 
       * The last element of the variable offset table points to the end of
       * the object. The variable offset array starts with zero, so we can
       * just access n_variable...
       */

      /* Write the offset to the end of the variable attributes table */
      buf->ptr = ((char *) (OR_VAR_ELEMENT_PTR (buf->buffer, attr_info->last_classrepr->n_variable)));
      or_put_offset_internal (buf, CAST_BUFLEN (ptr_varvals - buf->buffer - header_size), offset_size);
      buf->ptr = PTR_ALIGN (buf->ptr, INT_ALIGNMENT);
    }

      /* Record the length of the object */
      new_recdes->length = CAST_BUFLEN (ptr_varvals - buf->buffer);

      /* if not enough MVCC wasted space need to reallocate */
      if (ptr_varvals + mvcc_wasted_space < buf->endptr)
    {
      break;
    }

      /* 
       * if the longjmp status was anything other than ER_TF_BUFFER_OVERFLOW,
       * it represents an error condition and er_set will have been called
       */
    case ER_TF_BUFFER_OVERFLOW:

      status = S_DOESNT_FIT;

      /* 
       * Give a hint of the needed space. The hint is given as a negative
       * value in the record descriptor length. Make sure that this length
       * is larger than the current record descriptor area.
       */

      new_recdes->length = -expected_size;  /* set to negative */

      if (new_recdes->area_size > -new_recdes->length)
    {
      /* 
       * This may be an error. The estimated disk size is smaller
       * than the current record descriptor area size. For now assume
       * at least 20% above the current area descriptor. The main problem
       * is that heap_attrinfo_get_disksize () guess its size as much as
       * possible
       */
      new_recdes->length = -(int) (new_recdes->area_size * 1.20);
    }
      break;

    default:
      status = S_ERROR;
      break;
    }

  return status;
}

/*
 * heap_attrinfo_start_refoids () - Initialize an attribute information structure
 * with attributes that may reference other objects
 *   return: NO_ERROR
 *   class_oid(in): The class identifier of the instances where values
 *                  attributes values are going to be read.
 *   attr_info(in/out): The attribute information structure
 *
 * Note: Initialize an attribute information structure with attributes
 * that may reference other objects (OIDs).
 *
 * Note: The caller must call heap_attrinfo_end after he is done with
 * attribute information.
 */

static int
heap_attrinfo_start_refoids (THREAD_ENTRY * thread_p, OID * class_oid, HEAP_CACHE_ATTRINFO * attr_info)
{
  ATTR_ID guess_attrids[HEAP_GUESS_NUM_ATTRS_REFOIDS];
  ATTR_ID *set_attrids;
  int num_found_attrs;
  OR_CLASSREP *classrepr;
  int classrepr_cacheindex = -1;
  OR_ATTRIBUTE *search_attrepr;
  int i;
  int ret = NO_ERROR;

  attr_info->num_values = -1;

  /* 
   * Find the current representation of the class, then scan all its
   * attributes finding the ones that may reference objects
   */

  classrepr = heap_classrepr_get (thread_p, class_oid, NULL, NULL_REPRID, &classrepr_cacheindex);
  if (classrepr == NULL)
    {
      return ER_FAILED;
    }

  /* 
   * Go over the list of attributes until the desired attributes (OIDs, sets)
   * are found
   */

  if (classrepr->n_attributes > HEAP_GUESS_NUM_ATTRS_REFOIDS)
    {
      set_attrids = (ATTR_ID *) malloc (classrepr->n_attributes * sizeof (ATTR_ID));
      if (set_attrids == NULL)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1,
          classrepr->n_attributes * sizeof (ATTR_ID));
      heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);
      return ER_OUT_OF_VIRTUAL_MEMORY;
    }
    }
  else
    {
      set_attrids = guess_attrids;
    }

  for (i = 0, num_found_attrs = 0; i < classrepr->n_attributes; i++)
    {
      search_attrepr = &classrepr->attributes[i];
      if (tp_domain_references_objects (search_attrepr->domain) == true)
    {
      set_attrids[num_found_attrs++] = search_attrepr->id;
    }
    }

  ret = heap_attrinfo_start (thread_p, class_oid, num_found_attrs, set_attrids, attr_info);

  if (set_attrids != guess_attrids)
    {
      free_and_init (set_attrids);
    }

  heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);

  return ret;
}

/*
 * heap_attrinfo_start_with_index () -
 *   return:
 *   class_oid(in):
 *   class_recdes(in):
 *   attr_info(in):
 *   idx_info(in):
 */
int
heap_attrinfo_start_with_index (THREAD_ENTRY * thread_p, OID * class_oid, RECDES * class_recdes,
                HEAP_CACHE_ATTRINFO * attr_info, HEAP_IDX_ELEMENTS_INFO * idx_info)
{
  ATTR_ID guess_attrids[HEAP_GUESS_NUM_INDEXED_ATTRS];
  ATTR_ID *set_attrids;
  int num_found_attrs;
  OR_CLASSREP *classrepr = NULL;
  int classrepr_cacheindex = -1;
  OR_ATTRIBUTE *search_attrepr;
  int i, j;
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  int *num_btids;
  OR_INDEX *indexp;

  idx_info->has_single_col = 0;
  idx_info->has_multi_col = 0;
  idx_info->num_btids = 0;

  num_btids = &idx_info->num_btids;

  set_attrids = guess_attrids;
  attr_info->num_values = -1;   /* initialize attr_info */

  classrepr = heap_classrepr_get (thread_p, class_oid, class_recdes, NULL_REPRID, &classrepr_cacheindex);
  if (classrepr == NULL)
    {
      return ER_FAILED;
    }

  if (classrepr->n_attributes > HEAP_GUESS_NUM_INDEXED_ATTRS)
    {
      set_attrids = (ATTR_ID *) malloc (classrepr->n_attributes * sizeof (ATTR_ID));
      if (set_attrids == NULL)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1,
          classrepr->n_attributes * sizeof (ATTR_ID));
      heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);
      return ER_OUT_OF_VIRTUAL_MEMORY;
    }
    }
  else
    {
      set_attrids = guess_attrids;
    }

  /* 
   * Read the number of BTID's in this class
   */
  *num_btids = classrepr->n_indexes;

  for (j = 0; j < *num_btids; j++)
    {
      indexp = &classrepr->indexes[j];
      if (indexp->n_atts == 1)
    {
      idx_info->has_single_col = 1;
    }
      else if (indexp->n_atts > 1)
    {
      idx_info->has_multi_col = 1;
    }
      /* check for already found both */
      if (idx_info->has_single_col && idx_info->has_multi_col)
    {
      break;
    }
    }

  /* 
   * Go over the list of attrs until all indexed attributes (OIDs, sets)
   * are found
   */
  for (i = 0, num_found_attrs = 0, search_attrepr = classrepr->attributes; i < classrepr->n_attributes;
       i++, search_attrepr++)
    {
      if (search_attrepr->n_btids <= 0)
    {
      continue;
    }

      if (idx_info->has_single_col)
    {
      for (j = 0; j < *num_btids; j++)
        {
          indexp = &classrepr->indexes[j];
          if (indexp->n_atts == 1 && indexp->atts[0]->id == search_attrepr->id)
        {
          set_attrids[num_found_attrs++] = search_attrepr->id;
          break;
        }
        }
    }
    }               /* for (i = 0 ...) */

  if (idx_info->has_multi_col == 0 && num_found_attrs == 0)
    {
      /* initialize the attrinfo cache and return, there is nothing else to do */
      /* (void) memset(attr_info, '\0', sizeof (HEAP_CACHE_ATTRINFO)); */

      /* now set the num_values to -1 which indicates that this is an empty HEAP_CACHE_ATTRINFO and shouldn't be
       * operated on. */
      attr_info->num_values = -1;

      /* free the class representation */
      heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);
    }
  else
    {               /* num_found_attrs > 0 */
      /* initialize attribute information */
      attr_info->class_oid = *class_oid;
      attr_info->last_cacheindex = classrepr_cacheindex;
      attr_info->read_cacheindex = -1;
      attr_info->last_classrepr = classrepr;
      attr_info->read_classrepr = NULL;
      OID_SET_NULL (&attr_info->inst_oid);
      attr_info->inst_chn = NULL_CHN;
      attr_info->num_values = num_found_attrs;

      if (num_found_attrs <= 0)
    {
      attr_info->values = NULL;
    }
      else
    {
      attr_info->values =
        (HEAP_ATTRVALUE *) db_private_alloc (thread_p, (num_found_attrs * sizeof (HEAP_ATTRVALUE)));
      if (attr_info->values == NULL)
        {
          /* free the class representation */
          heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);
          attr_info->num_values = -1;
          goto error;
        }
    }

      /* 
       * Set the attribute identifier of the desired attributes in the value
       * attribute information, and indicates that the current value is
       * unitialized. That is, it has not been read, set or whatever.
       */
      for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      value->attrid = set_attrids[i];
      value->state = HEAP_UNINIT_ATTRVALUE;
      value->last_attrepr = NULL;
      value->read_attrepr = NULL;
    }

      /* 
       * Make last information to be recached for each individual attribute
       * value. Needed for WRITE and Default values
       */
      if (heap_attrinfo_recache_attrepr (attr_info, true) != NO_ERROR)
    {
      /* classrepr will be freed in heap_attrinfo_end */
      heap_attrinfo_end (thread_p, attr_info);
      goto error;
    }
    }

  if (set_attrids != guess_attrids)
    {
      free_and_init (set_attrids);
    }

  if (num_found_attrs == 0 && idx_info->has_multi_col)
    {
      return 1;
    }
  else
    {
      return num_found_attrs;
    }

  /* **** */
error:

  if (set_attrids != guess_attrids)
    {
      free_and_init (set_attrids);
    }

  return ER_FAILED;
}

/*
 * heap_classrepr_find_index_id () - Find the indicated index ID from the class repr
 *   return: ID of desired index ot -1 if an error occurred.
 *   classrepr(in): The class representation.
 *   btid(in): The BTID of the interested index.
 *
 * Note: Locate the desired index by matching it with the passed BTID.
 * Return the ID of the index if found.
 */
int
heap_classrepr_find_index_id (OR_CLASSREP * classrepr, const BTID * btid)
{
  int i;
  int id = -1;

  for (i = 0; i < classrepr->n_indexes; i++)
    {
      if (BTID_IS_EQUAL (&(classrepr->indexes[i].btid), btid))
    {
      id = i;
      break;
    }
    }

  return id;
}

/*
 * heap_attrinfo_start_with_btid () - Initialize an attribute information structure
 *   return: ID for the index which corresponds to the passed BTID.
 *           If an error occurred, a -1 is returned.
 *   class_oid(in): The class identifier of the instances where values
 *                  attributes values are going to be read.
 *   btid(in): The BTID of the interested index.
 *   attr_info(in/out): The attribute information structure
 *
 * Note: Initialize an attribute information structure, so that values
 * of instances can be retrieved based on the desired attributes.
 *
 * There are currently three functions which can be used to
 * initialize the attribute information structure; heap_attrinfo_start(),
 * heap_attrinfo_start_with_index() and this one.  This function determines
 * which attributes belong to the passed BTID and populate the
 * information structure on those attributes.
 *
 * The attrinfo structure is an structure where values of
 * instances can be read. For example an object is retrieved,
 * then some of its attributes are convereted to dbvalues and
 * placed in this structure.
 *
 * Note: The caller must call heap_attrinfo_end after he is done with
 * attribute information.
 */
int
heap_attrinfo_start_with_btid (THREAD_ENTRY * thread_p, OID * class_oid, BTID * btid, HEAP_CACHE_ATTRINFO * attr_info)
{
  ATTR_ID guess_attrids[HEAP_GUESS_NUM_INDEXED_ATTRS];
  ATTR_ID *set_attrids;
  OR_CLASSREP *classrepr = NULL;
  int i;
  int index_id = -1;
  int classrepr_cacheindex = -1;
  int num_found_attrs = 0;

  /* 
   *  We'll start by assuming that the number of attributes will fit into
   *  the preallocated array.
   */
  set_attrids = guess_attrids;

  attr_info->num_values = -1;   /* initialize attr_info */

  /* 
   *  Get the class representation so that we can access the indexes.
   */
  classrepr = heap_classrepr_get (thread_p, class_oid, NULL, NULL_REPRID, &classrepr_cacheindex);
  if (classrepr == NULL)
    {
      goto error;
    }

  /* 
   *  Get the index ID which corresponds to the BTID
   */
  index_id = heap_classrepr_find_index_id (classrepr, btid);
  if (index_id == -1)
    {
      goto error;
    }

  /* 
   *  Get the number of attributes associated with this index.
   *  Allocate a new attribute ID array if we have more attributes
   *  than will fit in the pre-allocated array.
   *  Fill the array with the attribute ID's
   *  Free the class representation.
   */
  num_found_attrs = classrepr->indexes[index_id].n_atts;
  if (num_found_attrs > HEAP_GUESS_NUM_INDEXED_ATTRS)
    {
      set_attrids = (ATTR_ID *) malloc (num_found_attrs * sizeof (ATTR_ID));
      if (set_attrids == NULL)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, num_found_attrs * sizeof (ATTR_ID));
      goto error;
    }
    }

  for (i = 0; i < num_found_attrs; i++)
    {
      set_attrids[i] = classrepr->indexes[index_id].atts[i]->id;
    }

  heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);

  /* 
   *  Get the attribute information for the collected ID's
   */
  if (num_found_attrs > 0)
    {
      if (heap_attrinfo_start (thread_p, class_oid, num_found_attrs, set_attrids, attr_info) != NO_ERROR)
    {
      goto error;
    }
    }

  /* 
   *  Free the attribute ID array if it was dynamically allocated
   */
  if (set_attrids != guess_attrids)
    {
      free_and_init (set_attrids);
    }

  return index_id;

  /* **** */
error:

  if (classrepr)
    {
      heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);
    }

  if (set_attrids != guess_attrids)
    {
      free_and_init (set_attrids);
    }

  return ER_FAILED;
}

#if defined (ENABLE_UNUSED_FUNCTION)
/*
 * heap_attrvalue_get_index () -
 *   return:
 *   value_index(in):
 *   attrid(in):
 *   n_btids(in):
 *   btids(in):
 *   idx_attrinfo(in):
 */
DB_VALUE *
heap_attrvalue_get_index (int value_index, ATTR_ID * attrid, int *n_btids, BTID ** btids,
              HEAP_CACHE_ATTRINFO * idx_attrinfo)
{
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */

  /* check to make sure the idx_attrinfo has been used, it should never be empty. */
  if (idx_attrinfo->num_values == -1)
    {
      return NULL;
    }

  if (value_index > idx_attrinfo->num_values || value_index < 0)
    {
      *n_btids = 0;
      *btids = NULL;
      *attrid = NULL_ATTRID;
      return NULL;
    }
  else
    {
      value = &idx_attrinfo->values[value_index];
      *n_btids = value->last_attrepr->n_btids;
      *btids = value->last_attrepr->btids;
      *attrid = value->attrid;
      return &value->dbvalue;
    }

}
#endif

/*
 * heap_midxkey_key_get () -
 *   return:
 *   recdes(in):
 *   midxkey(in/out):
 *   index(in):
 *   attrinfo(in):
 *   func_domain(in):
 *   key_domain(out):
 */
static DB_MIDXKEY *
heap_midxkey_key_get (RECDES * recdes, DB_MIDXKEY * midxkey, OR_INDEX * index, HEAP_CACHE_ATTRINFO * attrinfo,
              DB_VALUE * func_res, TP_DOMAIN * func_domain, TP_DOMAIN ** key_domain)
{
  char *nullmap_ptr;
  OR_ATTRIBUTE **atts;
  int num_atts, i, k;
  DB_VALUE value;
  OR_BUF buf;
  int error = NO_ERROR;
  TP_DOMAIN *set_domain = NULL;
  TP_DOMAIN *next_domain = NULL;

  assert (index != NULL);

  num_atts = index->n_atts;
  atts = index->atts;
  if (func_res)
    {
      num_atts = index->func_index_info->attr_index_start + 1;
    }
  assert (PTR_ALIGN (midxkey->buf, INT_ALIGNMENT) == midxkey->buf);

  or_init (&buf, midxkey->buf, -1);

  nullmap_ptr = midxkey->buf;
  or_advance (&buf, pr_midxkey_init_boundbits (nullmap_ptr, num_atts));
  k = 0;
  for (i = 0; i < num_atts && k < num_atts; i++)
    {
      if (index->func_index_info && (i == index->func_index_info->col_id))
    {
      assert (func_domain != NULL);

      if (!db_value_is_null (func_res))
        {
          (*(func_domain->type->index_writeval)) (&buf, func_res);
          OR_ENABLE_BOUND_BIT (nullmap_ptr, k);
        }

      if (key_domain != NULL)
        {
          if (k == 0)
        {
          assert (set_domain == NULL);
          set_domain = tp_domain_copy (func_domain, 0);
          if (set_domain == NULL)
            {
              assert (false);
              goto error;
            }
          next_domain = set_domain;
        }
          else
        {
          next_domain->next = tp_domain_copy (func_domain, 0);
          if (next_domain->next == NULL)
            {
              assert (false);
              goto error;
            }
          next_domain = next_domain->next;
        }
        }

      k++;
    }
      if (k == num_atts)
    {
      break;
    }
      error = heap_midxkey_get_value (recdes, atts[i], &value, attrinfo);
      if (error == NO_ERROR && !db_value_is_null (&value))
    {
      (*(atts[i]->domain->type->index_writeval)) (&buf, &value);
      OR_ENABLE_BOUND_BIT (nullmap_ptr, k);
    }

      if (DB_NEED_CLEAR (&value))
    {
      pr_clear_value (&value);
    }
      if (key_domain != NULL)
    {
      if (k == 0)
        {
          assert (set_domain == NULL);
          set_domain = tp_domain_copy (atts[i]->domain, 0);
          if (set_domain == NULL)
        {
          assert (false);
          goto error;
        }
          if (index->asc_desc[i] != 0)
        {
          set_domain->is_desc = 1;
        }
          next_domain = set_domain;
        }
      else
        {
          next_domain->next = tp_domain_copy (atts[i]->domain, 0);
          if (next_domain->next == NULL)
        {
          assert (false);
          goto error;
        }
          if (index->asc_desc[i] != 0)
        {
          next_domain->next->is_desc = 1;
        }
          next_domain = next_domain->next;
        }
    }
      k++;
    }

  midxkey->size = CAST_BUFLEN (buf.ptr - buf.buffer);
  midxkey->ncolumns = num_atts;
  midxkey->domain = NULL;

  if (key_domain != NULL)
    {
      *key_domain = tp_domain_construct (DB_TYPE_MIDXKEY, (DB_OBJECT *) 0, num_atts, 0, set_domain);

      if (*key_domain)
    {
      *key_domain = tp_domain_cache (*key_domain);
    }
      else
    {
      assert (false);
      goto error;
    }
    }

  return midxkey;

error:

  if (set_domain)
    {
      TP_DOMAIN *td, *next;

      for (td = set_domain, next = NULL; td != NULL; td = next)
    {
      next = td->next;
      tp_domain_free (td);
    }
    }

  return NULL;
}

/*
 * heap_midxkey_key_generate () -
 *   return:
 *   recdes(in):
 *   midxkey(in):
 *   att_ids(in):
 *   attrinfo(in):
 */
static DB_MIDXKEY *
heap_midxkey_key_generate (THREAD_ENTRY * thread_p, RECDES * recdes, DB_MIDXKEY * midxkey, int *att_ids,
               HEAP_CACHE_ATTRINFO * attrinfo, DB_VALUE * func_res, int func_col_id,
               int func_attr_index_start)
{
  char *nullmap_ptr;
  int num_vals, i, reprid, k;
  OR_ATTRIBUTE *att;
  DB_VALUE value;
  OR_BUF buf;
  int error = NO_ERROR;

  /* 
   * Make sure that we have the needed cached representation.
   */

  if (recdes != NULL)
    {
      reprid = or_rep_id (recdes);

      if (attrinfo->read_classrepr == NULL || attrinfo->read_classrepr->id != reprid)
    {
      /* Get the needed representation */
      if (heap_attrinfo_recache (thread_p, reprid, attrinfo) != NO_ERROR)
        {
          return NULL;
        }
    }
    }

  assert (PTR_ALIGN (midxkey->buf, INT_ALIGNMENT) == midxkey->buf);

  or_init (&buf, midxkey->buf, -1);

  nullmap_ptr = midxkey->buf;

  /* On constructing index */
  num_vals = attrinfo->num_values;
  if (func_res)
    {
      num_vals = func_attr_index_start + 1;
    }
  or_advance (&buf, pr_midxkey_init_boundbits (nullmap_ptr, num_vals));
  k = 0;
  for (i = 0; i < num_vals && k < num_vals; i++)
    {
      if (i == func_col_id)
    {
      if (!db_value_is_null (func_res))
        {
          TP_DOMAIN *domain = tp_domain_resolve_default ((DB_TYPE) func_res->domain.general_info.type);
          (*(domain->type->index_writeval)) (&buf, func_res);
          OR_ENABLE_BOUND_BIT (nullmap_ptr, k);
        }
      k++;
    }
      if (k == num_vals)
    {
      break;
    }
      att = heap_locate_attribute (att_ids[i], attrinfo);

      error = heap_midxkey_get_value (recdes, att, &value, attrinfo);
      if (error == NO_ERROR && !db_value_is_null (&value))
    {
      (*(att->domain->type->index_writeval)) (&buf, &value);
      OR_ENABLE_BOUND_BIT (nullmap_ptr, k);
    }

      if (DB_NEED_CLEAR (&value))
    {
      pr_clear_value (&value);
    }

      k++;
    }

  if (value.need_clear == true)
    {
      pr_clear_value (&value);
    }
  midxkey->size = CAST_BUFLEN (buf.ptr - buf.buffer);
  midxkey->ncolumns = num_vals;
  midxkey->domain = NULL;
  midxkey->min_max_val.position = -1;
  midxkey->min_max_val.type = MIN_COLUMN;

  return midxkey;
}

/*
 * heap_attrinfo_generate_key () - Generate a key from the attribute information.
 *   return: Pointer to DB_VALUE containing the key.
 *   n_atts(in): Size of attribute ID array.
 *   att_ids(in): Array of attribute ID's
 *   attr_info(in): Pointer to attribute information structure.  This
 *                  structure contains the BTID's, the attributes and their
 *                  values.
 *   recdes(in):
 *   db_valuep(in): Pointer to a DB_VALUE.  This db_valuep will be used to
 *                  contain the set key in the case of multi-column B-trees.
 *                  It is ignored for single-column B-trees.
 *   buf(in):
 *
 * Note: Return a key for the specified attribute ID's
 *
 * If n_atts=1, the key will be the value of that attribute
 * and we will return a pointer to that DB_VALUE.
 *
 * If n_atts>1, the key will be a sequence of the attribute
 * values.  The set will be constructed and contained with
 * the passed DB_VALUE.  A pointer to this DB_VALUE is returned.
 *
 * It is important for the caller to deallocate this memory
 * by calling pr_clear_value().
 */
DB_VALUE *
heap_attrinfo_generate_key (THREAD_ENTRY * thread_p, int n_atts, int *att_ids, int *atts_prefix_length,
                HEAP_CACHE_ATTRINFO * attr_info, RECDES * recdes, DB_VALUE * db_valuep, char *buf,
                FUNCTION_INDEX_INFO * func_index_info)
{
  DB_VALUE *ret_valp;
  DB_VALUE *fi_res = NULL;
  int fi_attr_index_start = -1;
  int fi_col_id = -1;

  assert (DB_IS_NULL (db_valuep));

  if (func_index_info)
    {
      fi_attr_index_start = func_index_info->attr_index_start;
      fi_col_id = func_index_info->col_id;
      if (heap_eval_function_index (thread_p, func_index_info, n_atts, att_ids, attr_info, recdes, -1, db_valuep,
                    NULL, NULL) != NO_ERROR)
    {
      return NULL;
    }
      fi_res = db_valuep;
    }

  /* 
   *  Multi-column index.  The key is a sequence of the attribute values.
   *  Return a pointer to the attributes DB_VALUE.
   */
  if ((n_atts > 1 && func_index_info == NULL) || (func_index_info && (func_index_info->attr_index_start + 1) > 1))
    {
      DB_MIDXKEY midxkey;
      int midxkey_size = recdes->length;

      if (func_index_info != NULL)
    {
      /* this will allocate more than it is needed to store the key, but there is no decent way to calculate the
       * correct size */
      midxkey_size += OR_VALUE_ALIGNED_SIZE (fi_res);
    }

      /* Allocate storage for the buf of midxkey */
      if (midxkey_size > DBVAL_BUFSIZE)
    {
      midxkey.buf = (char *) db_private_alloc (thread_p, midxkey_size);
      if (midxkey.buf == NULL)
        {
          return NULL;
        }
    }
      else
    {
      midxkey.buf = buf;
    }

      if (heap_midxkey_key_generate (thread_p, recdes, &midxkey, att_ids, attr_info, fi_res, fi_col_id,
                     fi_attr_index_start) == NULL)
    {
      return NULL;
    }

      (void) pr_clear_value (db_valuep);

      db_make_midxkey (db_valuep, &midxkey);

      if (midxkey_size > DBVAL_BUFSIZE)
    {
      db_valuep->need_clear = true;
    }

      ret_valp = db_valuep;
    }
  else
    {
      /* 
       *  Single-column index.  The key is simply the value of the attribute.
       *  Return a pointer to the attributes DB_VALUE.
       */
      if (func_index_info)
    {
      ret_valp = db_valuep;
      return ret_valp;
    }

      ret_valp = heap_attrinfo_access (att_ids[0], attr_info);
      if (ret_valp != NULL && atts_prefix_length && n_atts == 1)
    {
      if (*atts_prefix_length != -1 && QSTR_IS_ANY_CHAR_OR_BIT (DB_VALUE_DOMAIN_TYPE (ret_valp)))
        {
          /* prefix index */
          pr_clone_value (ret_valp, db_valuep);
          db_string_truncate (db_valuep, *atts_prefix_length);
          ret_valp = db_valuep;
        }
    }
    }

  return ret_valp;
}

/*
 * heap_attrvalue_get_key () - Get B-tree key from attribute value(s)
 *   return: Pointer to DB_VALUE containing the key.
 *   btid_index(in): Index into an array of BTID's from the OR_CLASSREP
 *                   structure contained in idx_attrinfo.
 *   idx_attrinfo(in): Pointer to attribute information structure.  This
 *                     structure contains the BTID's, the attributes and their
 *                     values.
 *   recdes(in):
 *   btid(out): Pointer to a BTID.  The value of the current BTID
 *              will be returned.
 *   db_value(in): Pointer to a DB_VALUE.  This db_value will be used to
 *                 contain the set key in the case of multi-column B-trees.
 *                 It is ignored for single-column B-trees.
 *   buf(in):
 *   func_preds(in): cached function index expressions
 *   key_domain(out): domain of key
 *
 * Note: Return a B-tree key for the specified B-tree ID.
 *
 * If the specified B-tree ID is associated with a single
 * attribute the key will be the value of that attribute
 * and we will return a pointer to that DB_VALUE.
 *
 * If the BTID is associated with multiple attributes the
 * key will be a set containing the values of the attributes.
 * The set will be constructed and contained within the
 * passed DB_VALUE.  A pointer to this DB_VALUE is returned.
 * It is important for the caller to deallocate this memory
 * by calling pr_clear_value().
 */
DB_VALUE *
heap_attrvalue_get_key (THREAD_ENTRY * thread_p, int btid_index, HEAP_CACHE_ATTRINFO * idx_attrinfo, RECDES * recdes,
            BTID * btid, DB_VALUE * db_value, char *buf, FUNC_PRED_UNPACK_INFO * func_indx_pred,
            TP_DOMAIN ** key_domain)
{
  OR_INDEX *index;
  int n_atts, reprid;
  DB_VALUE *ret_val = NULL;
  DB_VALUE *fi_res = NULL;
  TP_DOMAIN *fi_domain = NULL;

  assert (DB_IS_NULL (db_value));

  /* 
   *  check to make sure the idx_attrinfo has been used, it should
   *  never be empty.
   */
  if ((idx_attrinfo->num_values == -1) || (btid_index >= idx_attrinfo->last_classrepr->n_indexes))
    {
      return NULL;
    }

  /* 
   * Make sure that we have the needed cached representation.
   */
  if (recdes != NULL)
    {
      reprid = or_rep_id (recdes);

      if (idx_attrinfo->read_classrepr == NULL || idx_attrinfo->read_classrepr->id != reprid)
    {
      /* Get the needed representation */
      if (heap_attrinfo_recache (thread_p, reprid, idx_attrinfo) != NO_ERROR)
        {
          return NULL;
        }
    }
    }

  index = &(idx_attrinfo->last_classrepr->indexes[btid_index]);
  n_atts = index->n_atts;
  *btid = index->btid;

  /* is function index */
  if (index->func_index_info)
    {
      if (heap_eval_function_index (thread_p, NULL, -1, NULL, idx_attrinfo, recdes, btid_index, db_value,
                    func_indx_pred, &fi_domain) != NO_ERROR)
    {
      return NULL;
    }
      fi_res = db_value;
    }

  /* 
   *  Multi-column index.  Construct the key as a sequence of attribute
   *  values.  The sequence is contained in the passed DB_VALUE.  A
   *  pointer to this DB_VALUE is returned.
   */
  if ((n_atts > 1 && recdes != NULL && index->func_index_info == NULL)
      || (index->func_index_info && (index->func_index_info->attr_index_start + 1) > 1))
    {
      DB_MIDXKEY midxkey;
      int midxkey_size = recdes->length;

      if (index->func_index_info != NULL)
    {
      /* this will allocate more than it is needed to store the key, but there is no decent way to calculate the
       * correct size */
      midxkey_size += OR_VALUE_ALIGNED_SIZE (fi_res);
    }

      /* Allocate storage for the buf of midxkey */
      if (midxkey_size > DBVAL_BUFSIZE)
    {
      midxkey.buf = (char *) db_private_alloc (thread_p, midxkey_size);
      if (midxkey.buf == NULL)
        {
          return NULL;
        }
    }
      else
    {
      midxkey.buf = buf;
    }

      midxkey.min_max_val.position = -1;

      if (heap_midxkey_key_get (recdes, &midxkey, index, idx_attrinfo, fi_res, fi_domain, key_domain) == NULL)
    {
      return NULL;
    }

      (void) pr_clear_value (db_value);

      db_make_midxkey (db_value, &midxkey);

      if (midxkey_size > DBVAL_BUFSIZE)
    {
      db_value->need_clear = true;
    }

      ret_val = db_value;
    }
  else
    {
      /* 
       *  Single-column index.  The key is simply the value of the attribute.
       *  Return a pointer to the attributes DB_VALUE.
       */

      /* Find the matching attribute identified by the attribute ID */
      if (fi_res)
    {
      ret_val = fi_res;
      if (key_domain != NULL)
        {
          assert (fi_domain != NULL);
          *key_domain = tp_domain_cache (fi_domain);
        }
      return ret_val;
    }
      ret_val = heap_attrinfo_access (index->atts[0]->id, idx_attrinfo);

      if (ret_val != NULL && index->attrs_prefix_length != NULL && index->attrs_prefix_length[0] != -1)
    {
      if (QSTR_IS_ANY_CHAR_OR_BIT (DB_VALUE_DOMAIN_TYPE (ret_val)))
        {
          pr_clone_value (ret_val, db_value);
          db_string_truncate (db_value, index->attrs_prefix_length[0]);
          ret_val = db_value;
        }
    }

      if (key_domain != NULL)
    {
      if (index->attrs_prefix_length != NULL && index->attrs_prefix_length[0] != -1)
        {
          TP_DOMAIN *attr_dom;
          TP_DOMAIN *prefix_dom;
          DB_TYPE attr_type;

          attr_type = TP_DOMAIN_TYPE (index->atts[0]->domain);

          assert (QSTR_IS_ANY_CHAR_OR_BIT (attr_type));

          attr_dom = index->atts[0]->domain;

          prefix_dom =
        tp_domain_find_charbit (attr_type, TP_DOMAIN_CODESET (attr_dom), TP_DOMAIN_COLLATION (attr_dom),
                    TP_DOMAIN_COLLATION_FLAG (attr_dom), attr_dom->precision, attr_dom->is_desc);

          if (prefix_dom == NULL)
        {
          prefix_dom = tp_domain_construct (attr_type, NULL, index->attrs_prefix_length[0], 0, NULL);
          if (prefix_dom != NULL)
            {
              prefix_dom->codeset = TP_DOMAIN_CODESET (attr_dom);
              prefix_dom->collation_id = TP_DOMAIN_COLLATION (attr_dom);
              prefix_dom->collation_flag = TP_DOMAIN_COLLATION_FLAG (attr_dom);
              prefix_dom->is_desc = attr_dom->is_desc;
            }
        }

          if (prefix_dom == NULL)
        {
          return NULL;
        }
          else
        {
          *key_domain = tp_domain_cache (prefix_dom);
        }
        }
      else
        {
          *key_domain = tp_domain_cache (index->atts[0]->domain);
        }
    }
    }

  return ret_val;
}

/*
 * heap_indexinfo_get_btid () -
 *   return:
 *   btid_index(in):
 *   attrinfo(in):
 */
BTID *
heap_indexinfo_get_btid (int btid_index, HEAP_CACHE_ATTRINFO * attrinfo)
{
  if (btid_index != -1 && btid_index < attrinfo->last_classrepr->n_indexes)
    {
      return &(attrinfo->last_classrepr->indexes[btid_index].btid);
    }
  else
    {
      return NULL;
    }
}

/*
 * heap_indexinfo_get_num_attrs () -
 *   return:
 *   btid_index(in):
 *   attrinfo(in):
 */
int
heap_indexinfo_get_num_attrs (int btid_index, HEAP_CACHE_ATTRINFO * attrinfo)
{
  if (btid_index != -1 && btid_index < attrinfo->last_classrepr->n_indexes)
    {
      return attrinfo->last_classrepr->indexes[btid_index].n_atts;
    }
  else
    {
      return 0;
    }
}

/*
 * heap_indexinfo_get_attrids () -
 *   return: NO_ERROR
 *   btid_index(in):
 *   attrinfo(in):
 *   attrids(in):
 */
int
heap_indexinfo_get_attrids (int btid_index, HEAP_CACHE_ATTRINFO * attrinfo, ATTR_ID * attrids)
{
  int i;
  int ret = NO_ERROR;

  if (btid_index != -1 && (btid_index < attrinfo->last_classrepr->n_indexes))
    {
      for (i = 0; i < attrinfo->last_classrepr->indexes[btid_index].n_atts; i++)
    {
      attrids[i] = attrinfo->last_classrepr->indexes[btid_index].atts[i]->id;
    }
    }

  return ret;
}

/*
 * heap_indexinfo_get_attrs_prefix_length () -
 *   return: NO_ERROR
 *   btid_index(in):
 *   attrinfo(in):
 *   keys_prefix_length(in/out):
 */
int
heap_indexinfo_get_attrs_prefix_length (int btid_index, HEAP_CACHE_ATTRINFO * attrinfo, int *attrs_prefix_length,
                    int len_attrs_prefix_length)
{
  int i, length = -1;
  int ret = NO_ERROR;

  if (attrs_prefix_length && len_attrs_prefix_length > 0)
    {
      for (i = 0; i < len_attrs_prefix_length; i++)
    {
      attrs_prefix_length[i] = -1;
    }
    }

  if (btid_index != -1 && (btid_index < attrinfo->last_classrepr->n_indexes))
    {
      if (attrinfo->last_classrepr->indexes[btid_index].attrs_prefix_length && attrs_prefix_length)
    {
      length = MIN (attrinfo->last_classrepr->indexes[btid_index].n_atts, len_attrs_prefix_length);
      for (i = 0; i < length; i++)
        {
          attrs_prefix_length[i] = attrinfo->last_classrepr->indexes[btid_index].attrs_prefix_length[i];
        }
    }
    }

  return ret;
}

/*
 * heap_get_index_with_name () - get BTID of index with name index_name
 * return : error code or NO_ERROR
 * thread_p (in) :
 * class_oid (in) : class OID
 * index_name (in): index name
 * btid (in/out)  : btid
 */
int
heap_get_index_with_name (THREAD_ENTRY * thread_p, OID * class_oid, const char *index_name, BTID * btid)
{
  OR_CLASSREP *classrep = NULL;
  int idx_in_cache, i;
  int error = NO_ERROR;

  BTID_SET_NULL (btid);

  /* get the class representation so that we can access the indexes */
  classrep = heap_classrepr_get (thread_p, class_oid, NULL, NULL_REPRID, &idx_in_cache);
  if (classrep == NULL)
    {
      return ER_FAILED;
    }

  for (i = 0; i < classrep->n_indexes; i++)
    {
      if (strcasecmp (classrep->indexes[i].btname, index_name) == 0)
    {
      BTID_COPY (btid, &classrep->indexes[i].btid);
      break;
    }
    }
  if (classrep != NULL)
    {
      heap_classrepr_free_and_init (classrep, &idx_in_cache);
    }

  return error;
}

/*
 * heap_get_indexinfo_of_btid () -
 *   return: NO_ERROR
 *   class_oid(in):
 *   btid(in):
 *   type(in):
 *   num_attrs(in):
 *   attr_ids(in):
 *   btnamepp(in);
 */
int
heap_get_indexinfo_of_btid (THREAD_ENTRY * thread_p, const OID * class_oid, const BTID * btid, BTREE_TYPE * type,
                int *num_attrs, ATTR_ID ** attr_ids, int **attrs_prefix_length, char **btnamepp,
                int *func_index_col_id)
{
  OR_CLASSREP *classrepp;
  OR_INDEX *indexp;
  int idx_in_cache, i, n = 0;
  int idx;
  int ret = NO_ERROR;

  /* initial value of output parameters */
  if (num_attrs)
    {
      *num_attrs = 0;
    }

  if (attr_ids)
    {
      *attr_ids = NULL;
    }

  if (btnamepp)
    {
      *btnamepp = NULL;
    }

  if (attrs_prefix_length)
    {
      *attrs_prefix_length = NULL;
    }

  if (func_index_col_id)
    {
      *func_index_col_id = -1;
    }

  /* get the class representation so that we can access the indexes */
  classrepp = heap_classrepr_get (thread_p, class_oid, NULL, NULL_REPRID, &idx_in_cache);
  if (classrepp == NULL)
    {
      goto exit_on_error;
    }

  /* get the idx of the index which corresponds to the BTID */
  idx = heap_classrepr_find_index_id (classrepp, btid);
  if (idx < 0)
    {
      goto exit_on_error;
    }
  indexp = &classrepp->indexes[idx];

  /* get the type of this index */
  if (type)
    {
      *type = indexp->type;
    }

  /* get the number of attributes associated with this index */
  if (num_attrs)
    {
      *num_attrs = n = indexp->n_atts;
    }
  /* allocate a new attribute ID array */
  if (attr_ids)
    {
      *attr_ids = (ATTR_ID *) db_private_alloc (thread_p, n * sizeof (ATTR_ID));

      if (*attr_ids == NULL)
    {
      goto exit_on_error;
    }

      /* fill the array with the attribute ID's */
      for (i = 0; i < n; i++)
    {
      (*attr_ids)[i] = indexp->atts[i]->id;
    }
    }

  if (btnamepp)
    {
      *btnamepp = strdup (indexp->btname);
    }

  if (attrs_prefix_length && indexp->type == BTREE_INDEX)
    {
      *attrs_prefix_length = (int *) db_private_alloc (thread_p, n * sizeof (int));

      if (*attrs_prefix_length == NULL)
    {
      goto exit_on_error;
    }

      for (i = 0; i < n; i++)
    {
      if (indexp->attrs_prefix_length != NULL)
        {
          (*attrs_prefix_length)[i] = indexp->attrs_prefix_length[i];
        }
      else
        {
          (*attrs_prefix_length)[i] = -1;
        }
    }
    }

  if (func_index_col_id && indexp->func_index_info)
    {
      *func_index_col_id = indexp->func_index_info->col_id;
    }

  /* free the class representation */
  heap_classrepr_free_and_init (classrepp, &idx_in_cache);

  return ret;

exit_on_error:

  if (attr_ids && *attr_ids)
    {
      db_private_free_and_init (thread_p, *attr_ids);
    }

  if (btnamepp && *btnamepp)
    {
      free_and_init (*btnamepp);
    }

  if (attrs_prefix_length)
    {
      if (*attrs_prefix_length)
    {
      db_private_free_and_init (thread_p, *attrs_prefix_length);
    }
      *attrs_prefix_length = NULL;
    }

  if (classrepp)
    {
      heap_classrepr_free_and_init (classrepp, &idx_in_cache);
    }

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_get_referenced_by () - Find objects referenced by given object
 *   return: int (object count or -1)
 *   class_oid(in):
 *   obj_oid(in): The object identifier
 *   recdes(in): Object disk representation
 *   max_oid_cnt(in/out): Size of OID list in OIDs
 *   oid_list(in): Set to the array of referenced OIDs
 *                 (This area can be realloc, thus, it should have been
 *                 with malloc)
 *
 * Note: This function finds object identifiers referenced by the
 * given instance. If OID references are stored in the given
 * OID list. If the oid_list is not large enough to hold the
 * number of instances, the area (i.e., oid_list) is expanded
 * using realloc. The number of OID references is returned by the
 * function.
 *
 * Note: The oid_list pointer should be freed by the caller.
 * Note: Nested-sets, that is, set-of-sets inside the object are not traced.
 * Note: This function does not remove duplicate oids from the list, the
 * caller is responsible for checking and removing them if needed.
 */
int
heap_get_referenced_by (THREAD_ENTRY * thread_p, OID * class_oid, const OID * obj_oid, RECDES * recdes,
            int *max_oid_cnt, OID ** oid_list)
{
  HEAP_CACHE_ATTRINFO attr_info;
  DB_TYPE dbtype;
  HEAP_ATTRVALUE *value;    /* Disk value Attr info for a particular attr */
  DB_VALUE db_value;
  DB_SET *set;
  OID *oid_ptr;         /* iterator on oid_list */
  OID *attr_oid;
  int oid_cnt;          /* number of OIDs fetched */
  int cnt;          /* set element count */
  int new_max_oid;
  int i, j;         /* loop counters */

  /* 
   * We don't support class references in this function
   */
  if (oid_is_root (class_oid))
    {
      return 0;
    }

  if ((heap_attrinfo_start_refoids (thread_p, class_oid, &attr_info) != NO_ERROR)
      || heap_attrinfo_read_dbvalues (thread_p, obj_oid, recdes, NULL, &attr_info) != NO_ERROR)
    {
      goto error;
    }

  if (*oid_list == NULL)
    {
      *max_oid_cnt = 0;
    }
  else if (*max_oid_cnt <= 0)
    {
      /* 
       * We better release oid_list since we do not know it size. This may
       * be a bug.
       */
      free_and_init (*oid_list);
      *max_oid_cnt = 0;
    }

  /* 
   * Now start searching the attributes that may reference objects
   */
  oid_cnt = 0;
  oid_ptr = *oid_list;

  for (i = 0; i < attr_info.num_values; i++)
    {
      value = &attr_info.values[i];
      dbtype = db_value_type (&value->dbvalue);
      if (dbtype == DB_TYPE_OID && !db_value_is_null (&value->dbvalue)
      && (attr_oid = db_get_oid (&value->dbvalue)) != NULL && !OID_ISNULL (attr_oid))
    {
      /* 
       * A simple attribute with reference an object (OID)
       */
      if (oid_cnt == *max_oid_cnt)
        {
          /* 
           * We need to expand the area to deposit more OIDs.
           * Use 50% of the current size for expansion and at least 10 OIDs
           */
          if (*max_oid_cnt <= 0)
        {
          *max_oid_cnt = 0;
          new_max_oid = attr_info.num_values;
        }
          else
        {
          new_max_oid = (int) (*max_oid_cnt * 1.5) + 1;
          if (new_max_oid < attr_info.num_values)
            {
              new_max_oid = attr_info.num_values;
            }
        }

          if (new_max_oid < 10)
        {
          new_max_oid = 10;
        }

          oid_ptr = (OID *) realloc (*oid_list, new_max_oid * sizeof (OID));
          if (oid_ptr == NULL)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, new_max_oid * sizeof (OID));
          goto error;
        }

          /* 
           * Set the pointers and advance to current area pointer
           */
          *oid_list = oid_ptr;
          oid_ptr += *max_oid_cnt;
          *max_oid_cnt = new_max_oid;
        }
      *oid_ptr = *attr_oid;
      oid_ptr++;
      oid_cnt++;
    }
      else
    {
      if (TP_IS_SET_TYPE (dbtype))
        {
          /* 
           * A set which may or may nor reference objects (OIDs)
           * Go through each element of the set
           */

          set = db_get_set (&value->dbvalue);
          cnt = db_set_size (set);

          for (j = 0; j < cnt; j++)
        {
          if (db_set_get (set, j, &db_value) != NO_ERROR)
            {
              goto error;
            }

          dbtype = db_value_type (&db_value);
          if (dbtype == DB_TYPE_OID && !db_value_is_null (&db_value)
              && (attr_oid = db_get_oid (&db_value)) != NULL && !OID_ISNULL (attr_oid))
            {
              if (oid_cnt == *max_oid_cnt)
            {
              /* 
               * We need to expand the area to deposit more OIDs.
               * Use 50% of the current size for expansion.
               */
              if (*max_oid_cnt <= 0)
                {
                  *max_oid_cnt = 0;
                  new_max_oid = attr_info.num_values;
                }
              else
                {
                  new_max_oid = (int) (*max_oid_cnt * 1.5) + 1;
                  if (new_max_oid < attr_info.num_values)
                {
                  new_max_oid = attr_info.num_values;
                }
                }
              if (new_max_oid < 10)
                {
                  new_max_oid = 10;
                }

              oid_ptr = (OID *) realloc (*oid_list, new_max_oid * sizeof (OID));
              if (oid_ptr == NULL)
                {
                  er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1,
                      new_max_oid * sizeof (OID));
                  goto error;
                }

              /* 
               * Set the pointers and advance to current area pointer
               */
              *oid_list = oid_ptr;
              oid_ptr += *max_oid_cnt;
              *max_oid_cnt = new_max_oid;
            }
              *oid_ptr = *attr_oid;
              oid_ptr++;
              oid_cnt++;
            }
        }
        }
    }
    }

  /* free object area if no OIDs were encountered */
  if (oid_cnt == 0)
    /* 
     * Unless we check whether *oid_list is NULL,
     * it may cause double-free of oid_list.
     */
    if (*oid_list != NULL)
      {
    free_and_init (*oid_list);
      }

  heap_attrinfo_end (thread_p, &attr_info);

  /* return number of OIDs fetched */
  return oid_cnt;

error:
  /* XXXXXXX */

  free_and_init (*oid_list);
  *max_oid_cnt = 0;
  heap_attrinfo_end (thread_p, &attr_info);

  return ER_FAILED;
}

/*
 * heap_prefetch () - Prefetch objects
 *   return: NO_ERROR
 *           fetch_area is set to point to fetching area
 *   class_oid(in): Class identifier for the instance oid
 *   oid(in): Object that must be fetched if its cached state is invalid
 *   prefetch(in): Prefetch structure
 *
 */
int
heap_prefetch (THREAD_ENTRY * thread_p, OID * class_oid, const OID * oid, LC_COPYAREA_DESC * prefetch)
{
  VPID vpid;
  PAGE_PTR pgptr = NULL;
  int round_length;
  INT16 right_slotid, left_slotid;
  HEAP_DIRECTION direction;
  SCAN_CODE scan;
  int ret = NO_ERROR;

  /* 
   * Prefetch other instances (i.e., neighbors) stored on the same page
   * of the given object OID. Relocated instances and instances in overflow are
   * not prefetched, nor instances that do not belong to the given class.
   * Prefetching stop once an error, such as out of space, is encountered.
   */

  vpid.volid = oid->volid;
  vpid.pageid = oid->pageid;

  pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, S_LOCK, NULL, NULL);
  if (pgptr == NULL)
    {
      assert (er_errid () != NO_ERROR);
      ret = er_errid ();
      if (ret == ER_PB_BAD_PAGEID)
    {
      ret = ER_HEAP_UNKNOWN_OBJECT;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 3, oid->volid, oid->pageid, oid->slotid);
    }

      /* 
       * Problems getting the page.. forget about prefetching...
       */
      return ret;
    }

  right_slotid = oid->slotid;
  left_slotid = oid->slotid;
  direction = HEAP_DIRECTION_BOTH;

  while (direction != HEAP_DIRECTION_NONE)
    {
      /* 
       * Don't include the desired object again, forwarded instances, nor
       * instances that belong to other classes
       */

      /* Check to the right */
      if (direction == HEAP_DIRECTION_RIGHT || direction == HEAP_DIRECTION_BOTH)
    {
      scan = spage_next_record (pgptr, &right_slotid, prefetch->recdes, COPY);
      if (scan == S_SUCCESS && spage_get_record_type (pgptr, right_slotid) == REC_HOME)
        {
          prefetch->mobjs->num_objs++;
          COPY_OID (&((*prefetch->obj)->class_oid), class_oid);
          (*prefetch->obj)->oid.volid = oid->volid;
          (*prefetch->obj)->oid.pageid = oid->pageid;
          (*prefetch->obj)->oid.slotid = right_slotid;
          (*prefetch->obj)->length = prefetch->recdes->length;
          (*prefetch->obj)->offset = *prefetch->offset;
          (*prefetch->obj)->operation = LC_FETCH;
          (*prefetch->obj) = LC_NEXT_ONEOBJ_PTR_IN_COPYAREA (*prefetch->obj);
          round_length = DB_ALIGN (prefetch->recdes->length, HEAP_MAX_ALIGN);
          *prefetch->offset += round_length;
          prefetch->recdes->data += round_length;
          prefetch->recdes->area_size -= (round_length + sizeof (*(*prefetch->obj)));
        }
      else if (scan != S_SUCCESS)
        {
          /* Stop prefetching objects from the right */
          direction = ((direction == HEAP_DIRECTION_BOTH) ? HEAP_DIRECTION_LEFT : HEAP_DIRECTION_NONE);
        }
    }

      /* Check to the left */
      if (direction == HEAP_DIRECTION_LEFT || direction == HEAP_DIRECTION_BOTH)
    {
      scan = spage_previous_record (pgptr, &left_slotid, prefetch->recdes, COPY);
      if (scan == S_SUCCESS && left_slotid != HEAP_HEADER_AND_CHAIN_SLOTID
          && spage_get_record_type (pgptr, left_slotid) == REC_HOME)
        {
          prefetch->mobjs->num_objs++;
          COPY_OID (&((*prefetch->obj)->class_oid), class_oid);
          (*prefetch->obj)->oid.volid = oid->volid;
          (*prefetch->obj)->oid.pageid = oid->pageid;
          (*prefetch->obj)->oid.slotid = left_slotid;
          (*prefetch->obj)->length = prefetch->recdes->length;
          (*prefetch->obj)->offset = *prefetch->offset;
          (*prefetch->obj)->operation = LC_FETCH;
          (*prefetch->obj) = LC_NEXT_ONEOBJ_PTR_IN_COPYAREA (*prefetch->obj);
          round_length = DB_ALIGN (prefetch->recdes->length, HEAP_MAX_ALIGN);
          *prefetch->offset += round_length;
          prefetch->recdes->data += round_length;
          prefetch->recdes->area_size -= (round_length + sizeof (*(*prefetch->obj)));
        }
      else if (scan != S_SUCCESS)
        {
          /* Stop prefetching objects from the right */
          direction = ((direction == HEAP_DIRECTION_BOTH) ? HEAP_DIRECTION_RIGHT : HEAP_DIRECTION_NONE);
        }
    }
    }

  pgbuf_unfix_and_init (thread_p, pgptr);

  return ret;
}

static DISK_ISVALID
heap_check_all_pages_by_heapchain (THREAD_ENTRY * thread_p, HFID * hfid, HEAP_CHKALL_RELOCOIDS * chk_objs,
                   INT32 * num_checked)
{
  VPID vpid;
  VPID *vpidptr_ofpgptr;
  INT32 npages = 0;
  DISK_ISVALID valid_pg = DISK_VALID;
  bool spg_error = false;
  PGBUF_WATCHER pg_watcher;
  PGBUF_WATCHER old_pg_watcher;

  PGBUF_INIT_WATCHER (&pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&old_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;

  while (!VPID_ISNULL (&vpid) && valid_pg == DISK_VALID)
    {
      npages++;

      valid_pg = file_check_vpid (thread_p, &hfid->vfid, &vpid);
      if (valid_pg != DISK_VALID)
    {
      break;
    }

      pg_watcher.pgptr =
    heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE_PREVENT_DEALLOC, S_LOCK, NULL, &pg_watcher);
      if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }
      if (pg_watcher.pgptr == NULL)
    {
      /* something went wrong, return */
      valid_pg = DISK_ERROR;
      break;
    }
#ifdef SPAGE_DEBUG
      if (spage_check (thread_p, pg_watcher.pgptr) != NO_ERROR)
    {
      /* if spage has an error, try to go on. but, this page is corrupted. */
      spg_error = true;
    }
#endif

      if (heap_vpid_next (thread_p, hfid, pg_watcher.pgptr, &vpid) != NO_ERROR)
    {
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
      /* something went wrong, return */
      valid_pg = DISK_ERROR;
      break;
    }

      vpidptr_ofpgptr = pgbuf_get_vpid_ptr (pg_watcher.pgptr);
      if (VPID_EQ (&vpid, vpidptr_ofpgptr))
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_CYCLE, 5, vpid.volid, vpid.pageid, hfid->vfid.volid,
          hfid->vfid.fileid, hfid->hpgid);
      VPID_SET_NULL (&vpid);
      valid_pg = DISK_ERROR;
    }

      if (chk_objs != NULL)
    {
      valid_pg = heap_chkreloc_next (thread_p, chk_objs, pg_watcher.pgptr);
    }

      pgbuf_replace_watcher (thread_p, &pg_watcher, &old_pg_watcher);
    }

  if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }
  assert (pg_watcher.pgptr == NULL);

  *num_checked = npages;
  return (spg_error == true) ? DISK_ERROR : valid_pg;
}

#if defined (SA_MODE)
/*
 * heap_file_map_chkreloc () - FILE_MAP_PAGE_FUNC to check relocations.
 *
 * return        : error code
 * thread_p (in) : thread entry
 * page (in)     : heap page pointer
 * stop (in)     : not used
 * args (in)     : HEAP_CHKALL_RELOCOIDS *
 */
static int
heap_file_map_chkreloc (THREAD_ENTRY * thread_p, PAGE_PTR * page, bool * stop, void *args)
{
  HEAP_CHKALL_RELOCOIDS *chk_objs = (HEAP_CHKALL_RELOCOIDS *) args;

  DISK_ISVALID valid = DISK_VALID;
  int error_code = NO_ERROR;

  valid = heap_chkreloc_next (thread_p, chk_objs, *page);
  if (valid == DISK_INVALID)
    {
      assert_release (false);
      return ER_FAILED;
    }
  else if (valid == DISK_ERROR)
    {
      ASSERT_ERROR_AND_SET (error_code);
      return error_code;
    }
  return NO_ERROR;
}

/*
 * heap_check_all_pages_by_file_table () - check relocations using file table
 *
 * return        : DISK_INVALID for unexpected errors, DISK_ERROR for expected errors, DISK_VALID for successful check
 * thread_p (in) : thread entry
 * hfid (in)     : heap file identifier
 * chk_objs (in) : check relocation context
 */
static DISK_ISVALID
heap_check_all_pages_by_file_table (THREAD_ENTRY * thread_p, HFID * hfid, HEAP_CHKALL_RELOCOIDS * chk_objs)
{
  int error_code = NO_ERROR;

  error_code =
    file_map_pages (thread_p, &hfid->vfid, PGBUF_LATCH_READ, PGBUF_UNCONDITIONAL_LATCH, heap_file_map_chkreloc,
            chk_objs);
  if (error_code == ER_FAILED)
    {
      assert_release (false);
      return DISK_INVALID;
    }
  else if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return DISK_ERROR;
    }
  return DISK_VALID;
}
#endif /* SA_MODE */

/*
 * heap_check_all_pages () - Validate all pages known by given heap vs file manger
 *   return: DISK_INVALID, DISK_VALID, DISK_ERROR
 *   hfid(in): : Heap identifier
 *
 * Note: Verify that all pages known by the given heap are valid. That
 * is, that they are valid from the point of view of the file manager.
 */
DISK_ISVALID
heap_check_all_pages (THREAD_ENTRY * thread_p, HFID * hfid)
{
  VPID vpid;            /* Page-volume identifier */
  PAGE_PTR pgptr = NULL;    /* Page pointer */
  HEAP_HDR_STATS *heap_hdr; /* Header of heap structure */
  RECDES hdr_recdes;        /* Header record descriptor */
  DISK_ISVALID valid_pg = DISK_VALID;
  DISK_ISVALID valid = DISK_VALID;
  INT32 npages = 0;
  int i;
  HEAP_CHKALL_RELOCOIDS chk;
  HEAP_CHKALL_RELOCOIDS *chk_objs = &chk;
#if defined (SA_MODE)
  int file_numpages;
#endif /* SA_MODE */

  valid_pg = heap_chkreloc_start (chk_objs);
  if (valid_pg != DISK_VALID)
    {
      chk_objs = NULL;
    }
  else
    {
      chk_objs->verify_not_vacuumed = true;
    }

  /* Scan every page of the heap to find out if they are valid */
  valid_pg = heap_check_all_pages_by_heapchain (thread_p, hfid, chk_objs, &npages);

#if defined (SA_MODE)
  if (file_get_num_user_pages (thread_p, &hfid->vfid, &file_numpages) != NO_ERROR)
    {
      ASSERT_ERROR ();
      return valid_pg == DISK_VALID ? DISK_ERROR : valid_pg;
    }
  if (file_numpages != -1 && file_numpages != npages)
    {
      DISK_ISVALID tmp_valid_pg = DISK_VALID;

      assert (false);
      if (chk_objs != NULL)
    {
      chk_objs->verify = false;
      (void) heap_chkreloc_end (chk_objs);

      tmp_valid_pg = heap_chkreloc_start (chk_objs);
    }

      /* 
       * Scan every page of the heap using allocset.
       * This is for getting more information of the corrupted pages.
       */
      tmp_valid_pg = heap_check_all_pages_by_file_table (thread_p, hfid, chk_objs);

      if (chk_objs != NULL)
    {
      if (tmp_valid_pg == DISK_VALID)
        {
          tmp_valid_pg = heap_chkreloc_end (chk_objs);
        }
      else
        {
          chk_objs->verify = false;
          (void) heap_chkreloc_end (chk_objs);
        }
    }

      if (npages != file_numpages)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_MISMATCH_NPAGES, 5, hfid->vfid.volid, hfid->vfid.fileid,
          hfid->hpgid, npages, file_numpages);
      valid_pg = DISK_INVALID;
    }
      if (valid_pg == DISK_VALID && tmp_valid_pg != DISK_VALID)
    {
      valid_pg = tmp_valid_pg;
    }
    }
  else
#endif /* SA_MODE */
    {
      if (chk_objs != NULL)
    {
      valid_pg = heap_chkreloc_end (chk_objs);
    }
    }

  if (valid_pg == DISK_VALID)
    {
      /* 
       * Check the statistics entries in the header
       */

      /* Fetch the header page of the heap file */
      vpid.volid = hfid->vfid.volid;
      vpid.pageid = hfid->hpgid;

      pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, S_LOCK, NULL, NULL);
      if (pgptr == NULL)
    {
      return DISK_ERROR;
    }

      (void) pgbuf_check_page_ptype (thread_p, pgptr, PAGE_HEAP);

      if (spage_get_record (thread_p, pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &hdr_recdes, PEEK) != S_SUCCESS)
    {
      /* Unable to peek heap header record */
      pgbuf_unfix_and_init (thread_p, pgptr);

      return DISK_ERROR;
    }

      heap_hdr = (HEAP_HDR_STATS *) hdr_recdes.data;
      for (i = 0; i < HEAP_NUM_BEST_SPACESTATS && valid_pg != DISK_ERROR; i++)
    {
      if (!VPID_ISNULL (&heap_hdr->estimates.best[i].vpid))
        {
          valid = file_check_vpid (thread_p, &hfid->vfid, &heap_hdr->estimates.best[i].vpid);
          if (valid != DISK_VALID)
        {
          valid_pg = valid;
          break;
        }
        }
    }

#if defined(SA_MODE)
      if (prm_get_integer_value (PRM_ID_HF_MAX_BESTSPACE_ENTRIES) > 0)
    {
      HEAP_STATS_ENTRY *ent;
      void *last;
      int rc;

      rc = pthread_mutex_lock (&heap_Bestspace->bestspace_mutex);

      last = NULL;
      while ((ent = (HEAP_STATS_ENTRY *) mht_get2 (heap_Bestspace->hfid_ht, hfid, &last)) != NULL)
        {
          assert_release (!VPID_ISNULL (&ent->best.vpid));
          if (!VPID_ISNULL (&ent->best.vpid))
        {
          valid_pg = file_check_vpid (thread_p, &hfid->vfid, &ent->best.vpid);
          if (valid_pg != DISK_VALID)
            {
              break;
            }
        }
          assert_release (ent->best.freespace > 0);
        }

      assert (mht_count (heap_Bestspace->vpid_ht) == mht_count (heap_Bestspace->hfid_ht));

      pthread_mutex_unlock (&heap_Bestspace->bestspace_mutex);
    }
#endif

      pgbuf_unfix_and_init (thread_p, pgptr);

      /* Need to check for the overflow pages.... */
    }

  return valid_pg;
}

DISK_ISVALID
heap_check_heap_file (THREAD_ENTRY * thread_p, HFID * hfid)
{
  FILE_TYPE file_type;
  VPID vpid;
  DISK_ISVALID rv = DISK_VALID;
#if !defined (NDEBUG)
  FILE_DESCRIPTORS fdes;
#endif /* !NDEBUG */

  if (file_get_type (thread_p, &hfid->vfid, &file_type) != NO_ERROR)
    {
      return DISK_ERROR;
    }
  if (file_type == FILE_UNKNOWN_TYPE || (file_type != FILE_HEAP && file_type != FILE_HEAP_REUSE_SLOTS))
    {
      assert_release (false);
      return DISK_INVALID;
    }

  if (heap_get_header_page (thread_p, hfid, &vpid) == NO_ERROR)
    {
      hfid->hpgid = vpid.pageid;

#if !defined (NDEBUG)
      if (file_descriptor_get (thread_p, &hfid->vfid, &fdes) == NO_ERROR && !OID_ISNULL (&fdes.heap.class_oid))
    {
      assert (lock_has_lock_on_object (&fdes.heap.class_oid, oid_Root_class_oid,
                       LOG_FIND_THREAD_TRAN_INDEX (thread_p), SCH_S_LOCK) == 1);
    }
#endif /* NDEBUG */
      rv = heap_check_all_pages (thread_p, hfid);
      if (rv == DISK_INVALID)
    {
      assert_release (false);
    }
      else if (rv == DISK_ERROR)
    {
      ASSERT_ERROR ();
    }
      return rv;
    }
  else
    {
      ASSERT_ERROR ();
      return DISK_ERROR;
    }
}

/*
 * heap_check_all_heaps () - Validate all pages of all known heap files
 *   return: DISK_INVALID, DISK_VALID, DISK_ERROR
 *
 * Note: Verify that all pages of all heap files are valid. That is,
 * that they are valid from the point of view of the file manager.
 */
DISK_ISVALID
heap_check_all_heaps (THREAD_ENTRY * thread_p)
{
  int error_code = NO_ERROR;
  HFID hfid;
  DISK_ISVALID allvalid = DISK_VALID;
  DISK_ISVALID valid = DISK_VALID;
  VFID vfid = VFID_INITIALIZER;
  OID class_oid = OID_INITIALIZER;

  while (true)
    {
      /* Go to each file, check only the heap files */
      error_code = file_tracker_interruptable_iterate (thread_p, FILE_HEAP, &vfid, &class_oid);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit_on_error;
    }
      if (VFID_ISNULL (&vfid))
    {
      /* no more heap files */
      break;
    }

      hfid.vfid = vfid;
      valid = heap_check_heap_file (thread_p, &hfid);
      if (valid == DISK_ERROR)
    {
      goto exit_on_error;
    }
      if (valid != DISK_VALID)
    {
      allvalid = valid;
    }
    }
  assert (OID_ISNULL (&class_oid));

  return allvalid;

exit_on_error:
  if (!OID_ISNULL (&class_oid))
    {
      lock_unlock_object (thread_p, &class_oid, oid_Root_class_oid, SCH_S_LOCK, true);
    }

  return ((allvalid == DISK_VALID) ? DISK_ERROR : allvalid);
}

/*
 * heap_dump_hdr () - Dump heap file header
 *   return: NO_ERROR
 *   heap_hdr(in): Header structure
 */
static int
heap_dump_hdr (FILE * fp, HEAP_HDR_STATS * heap_hdr)
{
  int i, j;
  int avg_length;
  int ret = NO_ERROR;

  avg_length = ((heap_hdr->estimates.num_recs > 0)
        ? (int) ((heap_hdr->estimates.recs_sumlen / (float) heap_hdr->estimates.num_recs) + 0.9) : 0);

  fprintf (fp, "CLASS_OID = %2d|%4d|%2d, ", heap_hdr->class_oid.volid, heap_hdr->class_oid.pageid,
       heap_hdr->class_oid.slotid);
  fprintf (fp, "OVF_VFID = %4d|%4d, NEXT_VPID = %4d|%4d\n", heap_hdr->ovf_vfid.volid, heap_hdr->ovf_vfid.fileid,
       heap_hdr->next_vpid.volid, heap_hdr->next_vpid.pageid);
  fprintf (fp, "unfill_space = %4d\n", heap_hdr->unfill_space);
  fprintf (fp, "Estimated: num_pages = %d, num_recs = %d,  avg reclength = %d\n", heap_hdr->estimates.num_pages,
       heap_hdr->estimates.num_recs, avg_length);
  fprintf (fp, "Estimated: num high best = %d, num others(not in array) high best = %d\n",
       heap_hdr->estimates.num_high_best, heap_hdr->estimates.num_other_high_best);
  fprintf (fp, "Hint of best set of vpids with head = %d\n", heap_hdr->estimates.head);

  for (j = 0, i = 0; i < HEAP_NUM_BEST_SPACESTATS; j++, i++)
    {
      if (j != 0 && j % 5 == 0)
    {
      fprintf (fp, "\n");
    }
      fprintf (fp, "%4d|%4d %4d,", heap_hdr->estimates.best[i].vpid.volid, heap_hdr->estimates.best[i].vpid.pageid,
           heap_hdr->estimates.best[i].freespace);
    }
  fprintf (fp, "\n");

  fprintf (fp, "Second best: num hints = %d, head of hints = %d, tail (next to insert) of hints = %d, num subs = %d\n",
       heap_hdr->estimates.num_second_best, heap_hdr->estimates.head_second_best,
       heap_hdr->estimates.tail_second_best, heap_hdr->estimates.num_substitutions);
  for (j = 0, i = 0; i < HEAP_NUM_BEST_SPACESTATS; j++, i++)
    {
      if (j != 0 && j % 5 == 0)
    {
      fprintf (fp, "\n");
    }
      fprintf (fp, "%4d|%4d,", heap_hdr->estimates.second_best[i].volid, heap_hdr->estimates.second_best[i].pageid);
    }
  fprintf (fp, "\n");

  fprintf (fp, "Last vpid = %4d|%4d\n", heap_hdr->estimates.last_vpid.volid, heap_hdr->estimates.last_vpid.pageid);

  fprintf (fp, "Next full search vpid = %4d|%4d\n", heap_hdr->estimates.full_search_vpid.volid,
       heap_hdr->estimates.full_search_vpid.pageid);

  return ret;
}

/*
 * heap_dump () - Dump heap file
 *   return:
 *   hfid(in): Heap file identifier
 *   dump_records(in): If true, objects are printed in ascii format, otherwise, the
 *              objects are not printed.
 *
 * Note: Dump a heap file. The objects are printed only when the value
 * of dump_records is true. This function is used for DEBUGGING PURPOSES.
 */
void
heap_dump (THREAD_ENTRY * thread_p, FILE * fp, HFID * hfid, bool dump_records)
{
  VPID vpid;            /* Page-volume identifier */
  HEAP_HDR_STATS *heap_hdr; /* Header of heap structure */
  RECDES hdr_recdes;        /* Header record descriptor */
  VFID ovf_vfid;
  OID oid;
  HEAP_SCANCACHE scan_cache;
  HEAP_CACHE_ATTRINFO attr_info;
  RECDES peek_recdes;
  FILE_DESCRIPTORS fdes;
  int ret = NO_ERROR;
  PGBUF_WATCHER pg_watcher;
  PGBUF_WATCHER old_pg_watcher;

  PGBUF_INIT_WATCHER (&pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&old_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  fprintf (fp, "\n\n*** DUMPING HEAP FILE: ");
  fprintf (fp, "volid = %d, Fileid = %d, Header-pageid = %d ***\n", hfid->vfid.volid, hfid->vfid.fileid, hfid->hpgid);
  (void) file_descriptor_dump (thread_p, &hfid->vfid, fp);

  /* Fetch the header page of the heap file */

  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;
  pg_watcher.pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, S_LOCK, NULL, &pg_watcher);
  if (pg_watcher.pgptr == NULL)
    {
      /* Unable to fetch heap header page */
      return;
    }

  /* Peek the header record to dump the statistics */

  if (spage_get_record (thread_p, pg_watcher.pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &hdr_recdes, PEEK) != S_SUCCESS)
    {
      /* Unable to peek heap header record */
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
      return;
    }

  heap_hdr = (HEAP_HDR_STATS *) hdr_recdes.data;
  ret = heap_dump_hdr (fp, heap_hdr);
  if (ret != NO_ERROR)
    {
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
      return;
    }

  VFID_COPY (&ovf_vfid, &heap_hdr->ovf_vfid);
  pgbuf_ordered_unfix (thread_p, &pg_watcher);

  /* now scan every page and dump it */
  vpid.volid = hfid->vfid.volid;
  vpid.pageid = hfid->hpgid;
  while (!VPID_ISNULL (&vpid))
    {
      pg_watcher.pgptr =
    heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE_PREVENT_DEALLOC, S_LOCK, NULL, &pg_watcher);
      if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }
      if (pg_watcher.pgptr == NULL)
    {
      /* something went wrong, return */
      return;
    }
      spage_dump (thread_p, fp, pg_watcher.pgptr, dump_records);
      (void) heap_vpid_next (thread_p, hfid, pg_watcher.pgptr, &vpid);
      pgbuf_replace_watcher (thread_p, &pg_watcher, &old_pg_watcher);
    }

  if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }
  assert (pg_watcher.pgptr == NULL);

  /* Dump file table configuration */
  if (file_dump (thread_p, &hfid->vfid, fp) != NO_ERROR)
    {
      ASSERT_ERROR ();
      return;
    }

  if (!VFID_ISNULL (&ovf_vfid))
    {
      /* There is an overflow file for this heap file */
      fprintf (fp, "\nOVERFLOW FILE INFORMATION FOR HEAP FILE\n\n");
      if (file_dump (thread_p, &ovf_vfid, fp) != NO_ERROR)
    {
      ASSERT_ERROR ();
      return;
    }
    }

  /* 
   * Dump schema definition
   */

  if (file_descriptor_get (thread_p, &hfid->vfid, &fdes) != NO_ERROR)
    {
      ASSERT_ERROR ();
      return;
    }

  if (!OID_ISNULL (&fdes.heap.class_oid))
    {
      if (heap_attrinfo_start (thread_p, &fdes.heap.class_oid, -1, NULL, &attr_info) != NO_ERROR)
    {
      return;
    }

      ret = heap_classrepr_dump (thread_p, fp, &fdes.heap.class_oid, attr_info.last_classrepr);
      if (ret != NO_ERROR)
    {
      heap_attrinfo_end (thread_p, &attr_info);
      return;
    }

      /* Dump individual Objects */
      if (dump_records == true)
    {
      if (heap_scancache_start (thread_p, &scan_cache, hfid, NULL, true, false, NULL) != NO_ERROR)
        {
          /* something went wrong, return */
          heap_attrinfo_end (thread_p, &attr_info);
          return;
        }

      OID_SET_NULL (&oid);
      oid.volid = hfid->vfid.volid;

      while (heap_next (thread_p, hfid, NULL, &oid, &peek_recdes, &scan_cache, PEEK) == S_SUCCESS)
        {
          fprintf (fp, "Object-OID = %2d|%4d|%2d,\n  Length on disk = %d,\n", oid.volid, oid.pageid, oid.slotid,
               peek_recdes.length);

          if (heap_attrinfo_read_dbvalues (thread_p, &oid, &peek_recdes, NULL, &attr_info) != NO_ERROR)
        {
          fprintf (fp, "  Error ... continue\n");
          continue;
        }
          heap_attrinfo_dump (thread_p, fp, &attr_info, false);
        }
      heap_scancache_end (thread_p, &scan_cache);
    }
      heap_attrinfo_end (thread_p, &attr_info);
    }
  else
    {
      /* boot_Db_parm.hfid */
    }

  fprintf (fp, "\n\n*** END OF DUMP FOR HEAP FILE ***\n\n");
}

/*
 * heap_dump_capacity () - dump heap file capacity
 *
 * return        : error code
 * thread_p (in) : thread entry
 * fp (in)       : output file
 * hfid (in)     : heap file identifier
 */
int
heap_dump_capacity (THREAD_ENTRY * thread_p, FILE * fp, const HFID * hfid)
{
  INT64 num_recs = 0;
  INT64 num_recs_relocated = 0;
  INT64 num_recs_inovf = 0;
  INT64 num_pages = 0;
  int avg_freespace = 0;
  int avg_freespace_nolast = 0;
  int avg_reclength = 0;
  int avg_overhead = 0;
  HEAP_CACHE_ATTRINFO attr_info;
  FILE_DESCRIPTORS fdes;

  int error_code = NO_ERROR;

  fprintf (fp, "IO_PAGESIZE = %d, DB_PAGESIZE = %d, Recv_overhead = %d\n", IO_PAGESIZE, DB_PAGESIZE,
       IO_PAGESIZE - DB_PAGESIZE);

  /* Go to each file, check only the heap files */
  error_code =
    heap_get_capacity (thread_p, hfid, &num_recs, &num_recs_relocated, &num_recs_inovf, &num_pages, &avg_freespace,
               &avg_freespace_nolast, &avg_reclength, &avg_overhead);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }
  fprintf (fp, "HFID:%d|%d|%d, Num_recs = %" PRId64 ", Num_reloc_recs = %" PRId64 ",\n    Num_recs_inovf = %" PRId64
       ", Avg_reclength = %d,\n    Num_pages = %" PRId64 ", Avg_free_space_per_page = %d,\n"
       "    Avg_free_space_per_page_without_lastpage = %d\n    Avg_overhead_per_page = %d\n",
       (int) hfid->vfid.volid, hfid->vfid.fileid, hfid->hpgid, num_recs, num_recs_relocated, num_recs_inovf,
       avg_reclength, num_pages, avg_freespace, avg_freespace_nolast, avg_overhead);

  /* Dump schema definition */
  error_code = file_descriptor_get (thread_p, &hfid->vfid, &fdes);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }

  if (!OID_ISNULL (&fdes.heap.class_oid))
    {
      error_code = heap_attrinfo_start (thread_p, &fdes.heap.class_oid, -1, NULL, &attr_info);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }
      (void) heap_classrepr_dump (thread_p, fp, &fdes.heap.class_oid, attr_info.last_classrepr);
      heap_attrinfo_end (thread_p, &attr_info);
    }
  else
    {
      /* boot_Db_parm.hfid */
    }

  fprintf (fp, "\n");
  return NO_ERROR;
}

/*
 *      Check consistency of heap from the point of view of relocation
 */

/*
 * heap_chkreloc_start () - Start validating consistency of relocated objects in
 *                        heap
 *   return: DISK_VALID, DISK_INVALID, DISK_ERROR
 *   chk(in): Structure for checking relocation objects
 *
 */
static DISK_ISVALID
heap_chkreloc_start (HEAP_CHKALL_RELOCOIDS * chk)
{
  chk->ht = mht_create ("Validate Relocation entries hash table", HEAP_CHK_ADD_UNFOUND_RELOCOIDS, oid_hash,
            oid_compare_equals);
  if (chk->ht == NULL)
    {
      chk->ht = NULL;
      chk->unfound_reloc_oids = NULL;
      chk->max_unfound_reloc = -1;
      chk->num_unfound_reloc = -1;
      return DISK_ERROR;
    }

  chk->unfound_reloc_oids = (OID *) malloc (sizeof (*chk->unfound_reloc_oids) * HEAP_CHK_ADD_UNFOUND_RELOCOIDS);
  if (chk->unfound_reloc_oids == NULL)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1,
          sizeof (*chk->unfound_reloc_oids) * HEAP_CHK_ADD_UNFOUND_RELOCOIDS);

      if (chk->ht != NULL)
    {
      mht_destroy (chk->ht);
    }

      chk->ht = NULL;
      chk->unfound_reloc_oids = NULL;
      chk->max_unfound_reloc = -1;
      chk->num_unfound_reloc = -1;
      return DISK_ERROR;
    }

  chk->max_unfound_reloc = HEAP_CHK_ADD_UNFOUND_RELOCOIDS;
  chk->num_unfound_reloc = 0;
  chk->verify = true;
  chk->verify_not_vacuumed = false;
  chk->not_vacuumed_res = DISK_VALID;

  return DISK_VALID;
}

/*
 * heap_chkreloc_end () - Finish validating consistency of relocated objects
 *                      in heap
 *   return: DISK_VALID, DISK_INVALID, DISK_ERROR
 *   chk(in): Structure for checking relocation objects
 *
 * Note: Scanning the unfound_reloc_oid list, remove those entries that
 * are also found in hash table (remove them from unfound_reloc
 * list and from hash table). At the end of the scan, if there
 * are any entries in either hash table or unfound_reloc_oid, the
 * heap is incosistent/corrupted.
 */
static DISK_ISVALID
heap_chkreloc_end (HEAP_CHKALL_RELOCOIDS * chk)
{
  HEAP_CHK_RELOCOID *forward;
  DISK_ISVALID valid_reloc = DISK_VALID;
  int i;

  if (chk->not_vacuumed_res != DISK_VALID)
    {
      valid_reloc = chk->not_vacuumed_res;
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_FOUND_NOT_VACUUMED, 0);
    }

  /* 
   * Check for any postponed unfound relocated OIDs that have not been
   * checked or found. If they are not in the hash table, it would be an
   * error. That is, we would have a relocated (content) object without an
   * object pointing to it. (relocation/home).
   */
  if (chk->verify == true)
    {
      for (i = 0; i < chk->num_unfound_reloc; i++)
    {
      forward = (HEAP_CHK_RELOCOID *) mht_get (chk->ht, &chk->unfound_reloc_oids[i]);
      if (forward != NULL)
        {
          /* 
           * The entry was found.
           * Remove the entry and the memory space
           */
          /* mht_rem() has been updated to take a function and an arg pointer that can be called on the entry
           * before it is removed.  We may want to take advantage of that here to free the memory associated with
           * the entry */
          if (mht_rem (chk->ht, &chk->unfound_reloc_oids[i], NULL, NULL) != NO_ERROR)
        {
          valid_reloc = DISK_ERROR;
        }
          else
        {
          free_and_init (forward);
        }
        }
      else
        {
          er_log_debug (ARG_FILE_LINE, "Unable to find relocation/home object for relocated_oid=%d|%d|%d\n",
                (int) chk->unfound_reloc_oids[i].volid, chk->unfound_reloc_oids[i].pageid,
                (int) chk->unfound_reloc_oids[i].slotid);
#if defined (SA_MODE)
          er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
          valid_reloc = DISK_INVALID;
#endif /* SA_MODE */
        }
    }
    }

  /* 
   * If there are entries in the hash table, it would be problems. That is,
   * the relocated (content) objects were not found. That is, the home object
   * points to a dangling content object, or what it points is not a
   * relocated (newhome) object.
   */

  if (mht_count (chk->ht) > 0)
    {
      (void) mht_map (chk->ht, heap_chkreloc_print_notfound, chk);
#if defined (SA_MODE)
      valid_reloc = DISK_INVALID;
#endif /* !SA_MODE */
    }

  mht_destroy (chk->ht);
  free_and_init (chk->unfound_reloc_oids);

  return valid_reloc;
}

/*
 * heap_chkreloc_print_notfound () - Print entry that does not have a relocated entry
 *   return: NO_ERROR
 *   ignore_reloc_oid(in): Key (relocated entry to real entry) of hash table
 *   ent(in): The entry associated with key (real oid)
 *   xchk(in): Structure for checking relocation objects
 *
 * Note: Print unfound relocated record information for this home
 * record with relocation address HEAP is inconsistent.
 */
static int
heap_chkreloc_print_notfound (const void *ignore_reloc_oid, void *ent, void *xchk)
{
  HEAP_CHK_RELOCOID *forward = (HEAP_CHK_RELOCOID *) ent;
  HEAP_CHKALL_RELOCOIDS *chk = (HEAP_CHKALL_RELOCOIDS *) xchk;

  if (chk->verify == true)
    {
      er_log_debug (ARG_FILE_LINE,
            "Unable to find relocated record with oid=%d|%d|%d for home object with oid=%d|%d|%d\n",
            (int) forward->reloc_oid.volid, forward->reloc_oid.pageid, (int) forward->reloc_oid.slotid,
            (int) forward->real_oid.volid, forward->real_oid.pageid, (int) forward->real_oid.slotid);
#if defined (SA_MODE)
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
#endif /* SA_MODE */
    }
  /* mht_rem() has been updated to take a function and an arg pointer that can be called on the entry before it is
   * removed.  We may want to take advantage of that here to free the memory associated with the entry */
  (void) mht_rem (chk->ht, &forward->reloc_oid, NULL, NULL);
  free_and_init (forward);

  return NO_ERROR;
}

/*
 * heap_chkreloc_next () - Verify consistency of relocation records on page heap
 *   return: DISK_VALID, DISK_INVALID, DISK_ERROR
 *   thread_p(in) : thread context
 *   chk(in): Structure for checking relocation objects
 *   pgptr(in): Page pointer
 *
 * Note: While scanning objects of given page:
 *              1: if a relocation record is found, we check if that record
 *                 has already been seen (i.e., if it is in unfound_relc
 *                 list),
 *                 if it has been seen, we remove the entry from the
 *                 unfound_relc_oid list.
 *                 if it has not been seen, we add an entry to hash table
 *                 from reloc_oid to real_oid
 *                 Note: for optimization reasons, we may not scan the
 *                 unfound_reloc if it is too long, in this case the entry is
 *                 added to hash table.
 *              2: if a newhome (relocated) record is found, we check if the
 *                 real record has already been seen (i.e., check hash table),
 *                 if it has been seen, we remove the entry from hash table
 *                 otherwise, we add an entry into the unfound_reloc list
 */

#define HEAP_CHKRELOC_UNFOUND_SHORT 5

static DISK_ISVALID
heap_chkreloc_next (THREAD_ENTRY * thread_p, HEAP_CHKALL_RELOCOIDS * chk, PAGE_PTR pgptr)
{
  HEAP_CHK_RELOCOID *forward;
  INT16 type = REC_UNKNOWN;
  RECDES recdes;
  OID oid, class_oid;
  OID *peek_oid;
  void *ptr;
  bool found;
  int i;

  if (chk->verify != true)
    {
      return DISK_VALID;
    }

  if (chk->verify_not_vacuumed && heap_get_class_oid_from_page (thread_p, pgptr, &class_oid) != NO_ERROR)
    {
      chk->not_vacuumed_res = DISK_ERROR;
      return DISK_ERROR;
    }

  oid.volid = pgbuf_get_volume_id (pgptr);
  oid.pageid = pgbuf_get_page_id (pgptr);
  oid.slotid = 0;       /* i.e., will get slot 1 */

  while (spage_next_record (pgptr, &oid.slotid, &recdes, PEEK) == S_SUCCESS)
    {
      if (oid.slotid == HEAP_HEADER_AND_CHAIN_SLOTID)
    {
      continue;
    }
      type = spage_get_record_type (pgptr, oid.slotid);

      switch (type)
    {
    case REC_RELOCATION:
      /* 
       * The record stored on the page is a relocation record,
       * get the new home for the record
       *
       * If we have already entries waiting to be check and the list is
       * not that big, check them. Otherwise, wait until the end for the
       * check since searching the list may be expensive
       */
      peek_oid = (OID *) recdes.data;
      found = false;
      if (chk->num_unfound_reloc < HEAP_CHKRELOC_UNFOUND_SHORT)
        {
          /* 
           * Go a head and check since the list is very short.
           */
          for (i = 0; i < chk->num_unfound_reloc; i++)
        {
          if (OID_EQ (&chk->unfound_reloc_oids[i], peek_oid))
            {
              /* 
               * Remove it from the unfound list
               */
              if ((i + 1) != chk->num_unfound_reloc)
            {
              chk->unfound_reloc_oids[i] = chk->unfound_reloc_oids[chk->num_unfound_reloc - 1];
            }
              chk->num_unfound_reloc--;
              found = true;
              break;
            }
        }
        }
      if (found == false)
        {
          /* 
           * Add it to hash table
           */
          forward = (HEAP_CHK_RELOCOID *) malloc (sizeof (HEAP_CHK_RELOCOID));
          if (forward == NULL)
        {
          /* 
           * Out of memory
           */
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, sizeof (HEAP_CHK_RELOCOID));

          return DISK_ERROR;
        }
          forward->real_oid = oid;
          forward->reloc_oid = *peek_oid;
          if (mht_put (chk->ht, &forward->reloc_oid, forward) == NULL)
        {
          /* 
           * Failure in mht_put
           */
          return DISK_ERROR;
        }
        }
      break;

    case REC_BIGONE:
      if (chk->verify_not_vacuumed)
        {
          MVCC_REC_HEADER rec_header;
          PAGE_PTR overflow_page;
          DISK_ISVALID tmp_valid;
          VPID overflow_vpid;
          OID *overflow_oid;

          /* get overflow page id */
          overflow_oid = (OID *) recdes.data;
          overflow_vpid.volid = overflow_oid->volid;
          overflow_vpid.pageid = overflow_oid->pageid;
          if (VPID_ISNULL (&overflow_vpid))
        {
          chk->not_vacuumed_res = DISK_ERROR;
          return DISK_ERROR;
        }

          /* fix page and get record */
          overflow_page =
        pgbuf_fix (thread_p, &overflow_vpid, OLD_PAGE, PGBUF_LATCH_READ, PGBUF_UNCONDITIONAL_LATCH);
          if (overflow_page == NULL)
        {
          chk->not_vacuumed_res = DISK_ERROR;
          return DISK_ERROR;
        }
          if (heap_get_mvcc_rec_header_from_overflow (overflow_page, &rec_header, &recdes) != NO_ERROR)
        {
          pgbuf_unfix_and_init (thread_p, overflow_page);
          chk->not_vacuumed_res = DISK_ERROR;
          return DISK_ERROR;
        }
          pgbuf_unfix_and_init (thread_p, overflow_page);

          /* check header */
          tmp_valid = vacuum_check_not_vacuumed_rec_header (thread_p, &oid, &class_oid, &rec_header, -1);
          switch (tmp_valid)
        {
        case DISK_VALID:
          break;
        case DISK_INVALID:
          chk->not_vacuumed_res = DISK_INVALID;
          break;
        case DISK_ERROR:
        default:
          chk->not_vacuumed_res = DISK_ERROR;
          return DISK_ERROR;
          break;
        }
        }
      break;

    case REC_HOME:
      if (chk->verify_not_vacuumed)
        {
          DISK_ISVALID tmp_valid = vacuum_check_not_vacuumed_recdes (thread_p, &oid, &class_oid,
                                     &recdes, -1);
          switch (tmp_valid)
        {
        case DISK_VALID:
          break;
        case DISK_INVALID:
          chk->not_vacuumed_res = DISK_INVALID;
          break;
        case DISK_ERROR:
        default:
          chk->not_vacuumed_res = DISK_ERROR;
          return DISK_ERROR;
          break;
        }
        }
      break;

    case REC_NEWHOME:
      if (chk->verify_not_vacuumed)
        {
          DISK_ISVALID tmp_valid = vacuum_check_not_vacuumed_recdes (thread_p, &oid, &class_oid,
                                     &recdes, -1);
          switch (tmp_valid)
        {
        case DISK_VALID:
          break;
        case DISK_INVALID:
          chk->not_vacuumed_res = DISK_INVALID;
          break;
        case DISK_ERROR:
        default:
          chk->not_vacuumed_res = DISK_ERROR;
          return DISK_ERROR;
          break;
        }
        }

      /* 
       * Remove the object from hash table or insert the object in unfound
       * reloc check list.
       */
      forward = (HEAP_CHK_RELOCOID *) mht_get (chk->ht, &oid);
      if (forward != NULL)
        {
          /* 
           * The entry was found.
           * Remove the entry and the memory space
           */
          /* mht_rem() has been updated to take a function and an arg pointer that can be called on the entry
           * before it is removed.  We may want to take advantage of that here to free the memory associated with
           * the entry */
          (void) mht_rem (chk->ht, &forward->reloc_oid, NULL, NULL);
          free_and_init (forward);
        }
      else
        {
          /* 
           * The entry is not in hash table.
           * Add entry into unfound_reloc list
           */
          if (chk->max_unfound_reloc <= chk->num_unfound_reloc)
        {
          /* 
           * Need to realloc the area. Add 100 OIDs to it
           */
          i = (sizeof (*chk->unfound_reloc_oids) * (chk->max_unfound_reloc + HEAP_CHK_ADD_UNFOUND_RELOCOIDS));

          ptr = realloc (chk->unfound_reloc_oids, i);
          if (ptr == NULL)
            {
              er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, (size_t) i);
              return DISK_ERROR;
            }
          else
            {
              chk->unfound_reloc_oids = (OID *) ptr;
              chk->max_unfound_reloc += HEAP_CHK_ADD_UNFOUND_RELOCOIDS;
            }
        }
          i = chk->num_unfound_reloc++;
          chk->unfound_reloc_oids[i] = oid;
        }
      break;

    case REC_MARKDELETED:
    case REC_DELETED_WILL_REUSE:
    default:
      break;
    }
    }

  return DISK_VALID;
}

/*
 * Chn guesses for class objects at clients
 */

/*
 * Note: Currently, we do not try to guess chn of instances at clients.
 *       We are just doing it for classes.
 *
 * We do not know if the object is cached on the client side at all, we
 * are just guessing that it is still cached if it was sent to it. This is
 * almost 100% true since classes are avoided during garbage collection.

 * Caller does not know the chn when the client is fetching instances of the
 * class without knowning the class_oid. That does not imply that the
 * class object is not cached on the workspace. The client just did not
 * know the class_oid of the given fetched object. The server finds it and
 * has to decide whether or not to sent the class object. If the server does
 * not send the class object, and the client does not have it; the client will
 * request the class object (another server call)
 */

/*
 * heap_chnguess_initialize () - Initalize structure of chn guesses at clients
 *   return: NO_ERROR
 *
 * Note: Initialize structures used to cache information of CHN guess
 * at client workspaces.
 * Note: We current maintain that information only for classes.
 */
static int
heap_chnguess_initialize (void)
{
  HEAP_CHNGUESS_ENTRY *entry;
  int i;
  int ret = NO_ERROR;

  if (heap_Guesschn != NULL)
    {
      ret = heap_chnguess_finalize ();
      if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }
    }

  heap_Guesschn_area.schema_change = false;
  heap_Guesschn_area.clock_hand = -1;
  heap_Guesschn_area.num_entries = HEAP_CLASSREPR_MAXCACHE;

  /* 
   * Start with at least the fude factor of clients. Make sure that every
   * bit is used.
   */
  heap_Guesschn_area.num_clients = logtb_get_number_of_total_tran_indices ();
  if (heap_Guesschn_area.num_clients < HEAP_CHNGUESS_FUDGE_MININDICES)
    {
      heap_Guesschn_area.num_clients = HEAP_CHNGUESS_FUDGE_MININDICES;
    }

  /* Make sure every single bit is used */
  heap_Guesschn_area.nbytes = HEAP_NBITS_TO_NBYTES (heap_Guesschn_area.num_clients);
  heap_Guesschn_area.num_clients = HEAP_NBYTES_TO_NBITS (heap_Guesschn_area.nbytes);

  /* Build the hash table from OID to CHN */
  heap_Guesschn_area.ht =
    mht_create ("Memory hash OID to chn at clients", HEAP_CLASSREPR_MAXCACHE, oid_hash, oid_compare_equals);
  if (heap_Guesschn_area.ht == NULL)
    {
      goto exit_on_error;
    }

  heap_Guesschn_area.entries =
    (HEAP_CHNGUESS_ENTRY *) malloc (sizeof (HEAP_CHNGUESS_ENTRY) * heap_Guesschn_area.num_entries);
  if (heap_Guesschn_area.entries == NULL)
    {
      ret = ER_OUT_OF_VIRTUAL_MEMORY;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 1, sizeof (HEAP_CHNGUESS_ENTRY) * heap_Guesschn_area.num_entries);
      mht_destroy (heap_Guesschn_area.ht);
      goto exit_on_error;
    }

  heap_Guesschn_area.bitindex = (unsigned char *) malloc (heap_Guesschn_area.nbytes * heap_Guesschn_area.num_entries);
  if (heap_Guesschn_area.bitindex == NULL)
    {
      ret = ER_OUT_OF_VIRTUAL_MEMORY;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 1,
          (size_t) (heap_Guesschn_area.nbytes * heap_Guesschn_area.num_entries));
      mht_destroy (heap_Guesschn_area.ht);
      free_and_init (heap_Guesschn_area.entries);
      goto exit_on_error;
    }

  /* 
   * Initialize every entry as not recently freed
   */
  for (i = 0; i < heap_Guesschn_area.num_entries; i++)
    {
      entry = &heap_Guesschn_area.entries[i];
      entry->idx = i;
      entry->chn = NULL_CHN;
      entry->recently_accessed = false;
      OID_SET_NULL (&entry->oid);
      entry->bits = &heap_Guesschn_area.bitindex[i * heap_Guesschn_area.nbytes];
      HEAP_NBYTES_CLEARED (entry->bits, heap_Guesschn_area.nbytes);
    }
  heap_Guesschn = &heap_Guesschn_area;

  return ret;

exit_on_error:

  return (ret == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_chnguess_realloc () - More clients that currently maintained
 *   return: NO_ERROR
 *
 * Note: Expand the chn_guess structures to support at least the number
 * currently connected clients.
 */
static int
heap_chnguess_realloc (void)
{
  int i;
  unsigned char *save_bitindex;
  int save_nbytes;
  HEAP_CHNGUESS_ENTRY *entry;
  int ret = NO_ERROR;

  if (heap_Guesschn == NULL)
    {
      return heap_chnguess_initialize ();
    }

  /* 
   * Save current information, so we can copy them at a alater point
   */
  save_bitindex = heap_Guesschn_area.bitindex;
  save_nbytes = heap_Guesschn_area.nbytes;

  /* 
   * Find the number of clients that need to be supported. Avoid small
   * increases since it is undesirable to realloc again. Increase by at least
   * the fudge factor.
   */

  heap_Guesschn->num_clients += HEAP_CHNGUESS_FUDGE_MININDICES;
  i = logtb_get_number_of_total_tran_indices ();

  if (heap_Guesschn->num_clients < i)
    {
      heap_Guesschn->num_clients = i + HEAP_CHNGUESS_FUDGE_MININDICES;
    }

  /* Make sure every single bit is used */
  heap_Guesschn_area.nbytes = HEAP_NBITS_TO_NBYTES (heap_Guesschn_area.num_clients);
  heap_Guesschn_area.num_clients = HEAP_NBYTES_TO_NBITS (heap_Guesschn_area.nbytes);

  heap_Guesschn_area.bitindex = (unsigned char *) malloc (heap_Guesschn_area.nbytes * heap_Guesschn_area.num_entries);
  if (heap_Guesschn_area.bitindex == NULL)
    {
      ret = ER_OUT_OF_VIRTUAL_MEMORY;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ret, 1,
          (size_t) (heap_Guesschn_area.nbytes * heap_Guesschn_area.num_entries));
      heap_Guesschn_area.bitindex = save_bitindex;
      heap_Guesschn_area.nbytes = save_nbytes;
      heap_Guesschn_area.num_clients = HEAP_NBYTES_TO_NBITS (save_nbytes);
      goto exit_on_error;
    }

  /* 
   * Now reset the bits for each entry
   */

  for (i = 0; i < heap_Guesschn_area.num_entries; i++)
    {
      entry = &heap_Guesschn_area.entries[i];
      entry->bits = &heap_Guesschn_area.bitindex[i * heap_Guesschn_area.nbytes];
      /* 
       * Copy the bits
       */
      memcpy (entry->bits, &save_bitindex[i * save_nbytes], save_nbytes);
      HEAP_NBYTES_CLEARED (&entry->bits[save_nbytes], heap_Guesschn_area.nbytes - save_nbytes);
    }
  /* 
   * Now throw previous storage
   */
  free_and_init (save_bitindex);

  return ret;

exit_on_error:

  return (ret == NO_ERROR && (ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_chnguess_finalize () - Finish chnguess information
 *   return: NO_ERROR
 *
 * Note: Destroy hash table and memory for entries.
 */
static int
heap_chnguess_finalize (void)
{
  int ret = NO_ERROR;

  if (heap_Guesschn == NULL)
    {
      return NO_ERROR;      /* nop */
    }

  mht_destroy (heap_Guesschn->ht);
  free_and_init (heap_Guesschn->entries);
  free_and_init (heap_Guesschn->bitindex);
  heap_Guesschn->ht = NULL;
  heap_Guesschn->schema_change = false;
  heap_Guesschn->clock_hand = 0;
  heap_Guesschn->num_entries = 0;
  heap_Guesschn->num_clients = 0;
  heap_Guesschn->nbytes = 0;

  heap_Guesschn = NULL;

  return ret;
}

/*
 * heap_stats_bestspace_initialize () - Initialize structure of best space
 *   return: NO_ERROR
 */
static int
heap_stats_bestspace_initialize (void)
{
  int ret = NO_ERROR;

  if (heap_Bestspace != NULL)
    {
      ret = heap_stats_bestspace_finalize ();
      if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }
    }

  heap_Bestspace = &heap_Bestspace_cache_area;

  pthread_mutex_init (&heap_Bestspace->bestspace_mutex, NULL);

  heap_Bestspace->num_stats_entries = 0;

  heap_Bestspace->hfid_ht =
    mht_create ("Memory hash HFID to {bestspace}", HEAP_STATS_ENTRY_MHT_EST_SIZE, heap_hash_hfid, heap_compare_hfid);
  if (heap_Bestspace->hfid_ht == NULL)
    {
      goto exit_on_error;
    }

  heap_Bestspace->vpid_ht =
    mht_create ("Memory hash VPID to {bestspace}", HEAP_STATS_ENTRY_MHT_EST_SIZE, heap_hash_vpid, heap_compare_vpid);
  if (heap_Bestspace->vpid_ht == NULL)
    {
      goto exit_on_error;
    }

  heap_Bestspace->num_alloc = 0;
  heap_Bestspace->num_free = 0;
  heap_Bestspace->free_list_count = 0;
  heap_Bestspace->free_list = NULL;

  return ret;

exit_on_error:

  return (ret == NO_ERROR) ? ER_FAILED : ret;
}

/*
 * heap_stats_bestspace_finalize () - Finish best space information
 *   return: NO_ERROR
 *
 * Note: Destroy hash table and memory for entries.
 */
static int
heap_stats_bestspace_finalize (void)
{
  HEAP_STATS_ENTRY *ent;
  int ret = NO_ERROR;

  if (heap_Bestspace == NULL)
    {
      return NO_ERROR;
    }

  if (heap_Bestspace->vpid_ht != NULL)
    {
      (void) mht_map_no_key (NULL, heap_Bestspace->vpid_ht, heap_stats_entry_free, NULL);
      while (heap_Bestspace->free_list_count > 0)
    {
      ent = heap_Bestspace->free_list;
      assert_release (ent != NULL);

      heap_Bestspace->free_list = ent->next;
      ent->next = NULL;

      free (ent);

      heap_Bestspace->free_list_count--;
    }
      assert_release (heap_Bestspace->free_list == NULL);
    }

  if (heap_Bestspace->vpid_ht != NULL)
    {
      mht_destroy (heap_Bestspace->vpid_ht);
      heap_Bestspace->vpid_ht = NULL;
    }

  if (heap_Bestspace->hfid_ht != NULL)
    {
      mht_destroy (heap_Bestspace->hfid_ht);
      heap_Bestspace->hfid_ht = NULL;
    }

  pthread_mutex_destroy (&heap_Bestspace->bestspace_mutex);

  heap_Bestspace = NULL;

  return ret;
}

/*
 * heap_chnguess_decache () - Decache a specific entry or all entries
 *   return: NO_ERROR
 *   oid(in): oid: class oid or NULL
 *            IF NULL implies all classes
 *
 * Note: Remove from the hash the entry associated with given oid. If
 * oid is NULL, all entries in hash are removed.
 * This function is called when a class is updated or during
 * rollback when a class was changed
 */
static int
heap_chnguess_decache (const OID * oid)
{
  HEAP_CHNGUESS_ENTRY *entry;
  int ret = NO_ERROR;

  if (heap_Guesschn == NULL)
    {
      return NO_ERROR;      /* nop */
    }

  if (oid == NULL)
    {
      (void) mht_map (heap_Guesschn->ht, heap_chnguess_remove_entry, NULL);
    }
  else
    {
      entry = (HEAP_CHNGUESS_ENTRY *) mht_get (heap_Guesschn->ht, oid);
      if (entry != NULL)
    {
      (void) heap_chnguess_remove_entry (oid, entry, NULL);
    }
    }

  if (heap_Guesschn->schema_change == true && oid == NULL)
    {
      heap_Guesschn->schema_change = false;
    }

  return ret;
}

/*
 * heap_chnguess_remove_entry () - Remove an entry from chnguess hash table
 *   return: NO_ERROR
 *   oid_key(in): Key (oid) of chnguess table
 *   ent(in): The entry of hash table
 *   xignore(in): Extra arguments (currently ignored)
 *
 * Note: Remove from the hash the given entry. The entry is marked as
 * for immediate reuse.
 */
static int
heap_chnguess_remove_entry (const void *oid_key, void *ent, void *xignore)
{
  HEAP_CHNGUESS_ENTRY *entry = (HEAP_CHNGUESS_ENTRY *) ent;

  /* mht_rem() has been updated to take a function and an arg pointer that can be called on the entry before it is
   * removed.  We may want to take advantage of that here to free the memory associated with the entry */
  (void) mht_rem (heap_Guesschn->ht, oid_key, NULL, NULL);
  OID_SET_NULL (&entry->oid);
  entry->chn = NULL_CHN;
  entry->recently_accessed = false;
  heap_Guesschn_area.clock_hand = entry->idx;

  return NO_ERROR;
}

#if defined (CUBRID_DEBUG)
/*
 * heap_chnguess_dump () - Dump current chnguess hash table
 *   return:
 *
 * Note: Dump all valid chnguess entries.
 */
void
heap_chnguess_dump (FILE * fp)
{
  int max_tranindex, tran_index, i;
  HEAP_CHNGUESS_ENTRY *entry;

  if (heap_Guesschn != NULL)
    {
      fprintf (fp, "*** Dump of CLASS_OID to CHNGUESS at clients *** \n");
      fprintf (fp, "Schema_change = %d, clock_hand = %d,\n", heap_Guesschn->schema_change, heap_Guesschn->clock_hand);
      fprintf (fp, "Nentries = %d, Nactive_entries = %u, maxnum of clients = %d, nbytes = %d\n",
           heap_Guesschn->num_entries, mht_count (heap_Guesschn->ht), heap_Guesschn->num_clients,
           heap_Guesschn->nbytes);
      fprintf (fp, "Hash Table = %p, Entries = %p, Bitindex = %p\n", heap_Guesschn->ht, heap_Guesschn->entries,
           heap_Guesschn->bitindex);

      max_tranindex = logtb_get_number_of_total_tran_indices ();
      for (i = 0; i < heap_Guesschn->num_entries; i++)
    {
      entry = &heap_Guesschn_area.entries[i];

      if (!OID_ISNULL (&entry->oid))
        {
          fprintf (fp, " \nEntry_id %d", entry->idx);
          fprintf (fp, "OID = %2d|%4d|%2d, chn = %d, recently_free = %d,", entry->oid.volid, entry->oid.pageid,
               entry->oid.slotid, entry->chn, entry->recently_accessed);

          /* Dump one bit at a time */
          for (tran_index = 0; tran_index < max_tranindex; tran_index++)
        {
          if (tran_index % 40 == 0)
            {
              fprintf (fp, "\n ");
            }
          else if (tran_index % 10 == 0)
            {
              fprintf (fp, " ");
            }
          fprintf (fp, "%d", HEAP_BIT_GET (entry->bits, tran_index) ? 1 : 0);
        }
          fprintf (fp, "\n");
        }
    }
    }
}
#endif /* CUBRID_DEBUG */

/*
 * heap_chnguess_get () - Guess chn of given oid for given tran index (at client)
 *   return:
 *   oid(in): OID from where to guess chn at client workspace
 *   tran_index(in): The client transaction index
 *
 * Note: Find/guess the chn of the given OID object at the workspace of
 * given client transaction index
 */
int
heap_chnguess_get (THREAD_ENTRY * thread_p, const OID * oid, int tran_index)
{
  int chn = NULL_CHN;
  HEAP_CHNGUESS_ENTRY *entry;

  if (csect_enter (thread_p, CSECT_HEAP_CHNGUESS, INF_WAIT) != NO_ERROR)
    {
      return NULL_CHN;
    }

  if (heap_Guesschn != NULL)
    {
      if (heap_Guesschn->num_clients <= tran_index)
    {
      if (heap_chnguess_realloc () != NO_ERROR)
        {
          csect_exit (thread_p, CSECT_HEAP_CHNGUESS);
          return NULL_CHN;
        }
    }

      /* 
       * Do we have this entry in hash table, if we do then check corresponding
       * bit for given client transaction index.
       */

      entry = (HEAP_CHNGUESS_ENTRY *) mht_get (heap_Guesschn->ht, oid);
      if (entry != NULL && HEAP_BIT_GET (entry->bits, tran_index))
    {
      chn = entry->chn;
    }
    }

  csect_exit (thread_p, CSECT_HEAP_CHNGUESS);

  return chn;
}

/*
 * heap_chnguess_put () - Oid object is in the process of been sent to client
 *   return: chn or NULL_CHN if not cached
 *   oid(in): object oid
 *   tran_index(in): The client transaction index
 *   chn(in): cache coherency number.
 *
 * Note: Cache the information that object oid with chn has been sent
 * to client with trans_index.
 * If the function fails, it returns NULL_CHN. This failure is
 * more like a warning since the chnguess is just a caching structure.
 */
int
heap_chnguess_put (THREAD_ENTRY * thread_p, const OID * oid, int tran_index, int chn)
{
  int i;
  bool can_continue;
  HEAP_CHNGUESS_ENTRY *entry;

  if (heap_Guesschn == NULL)
    {
      return NULL_CHN;
    }

  if (csect_enter (thread_p, CSECT_HEAP_CHNGUESS, INF_WAIT) != NO_ERROR)
    {
      return NULL_CHN;
    }

  if (heap_Guesschn->num_clients <= tran_index)
    {
      if (heap_chnguess_realloc () != NO_ERROR)
    {
      csect_exit (thread_p, CSECT_HEAP_CHNGUESS);
      return NULL_CHN;
    }
    }

  /* 
   * Is the entry already in the chnguess hash table ?
   */
  entry = (HEAP_CHNGUESS_ENTRY *) mht_get (heap_Guesschn->ht, oid);
  if (entry != NULL)
    {
      /* 
       * If the cache coherence number is different reset all client entries
       */
      if (entry->chn != chn)
    {
      HEAP_NBYTES_CLEARED (entry->bits, heap_Guesschn_area.nbytes);
      entry->chn = chn;
    }
    }
  else
    {
      /* 
       * Replace one of the entries that has not been used for a while.
       * Follow clock replacement algorithm.
       */
      can_continue = true;
      while (entry == NULL && can_continue == true)
    {
      can_continue = false;
      for (i = 0; i < heap_Guesschn->num_entries; i++)
        {
          /* 
           * Increase the clock to next entry
           */
          heap_Guesschn->clock_hand++;
          if (heap_Guesschn->clock_hand >= heap_Guesschn->num_entries)
        {
          heap_Guesschn->clock_hand = 0;
        }

          entry = &heap_Guesschn->entries[heap_Guesschn->clock_hand];
          if (entry->recently_accessed == true)
        {
          /* 
           * Set recently freed to false, so it can be replaced in next
           * if the entry is not referenced
           */
          entry->recently_accessed = false;
          entry = NULL;
          can_continue = true;
        }
          else
        {
          entry->oid = *oid;
          entry->chn = chn;
          HEAP_NBYTES_CLEARED (entry->bits, heap_Guesschn_area.nbytes);
          break;
        }
        }
    }
    }

  /* 
   * Now set the desired client transaction index bit
   */
  if (entry != NULL)
    {
      HEAP_BIT_SET (entry->bits, tran_index);
      entry->recently_accessed = true;
    }
  else
    {
      chn = NULL_CHN;
    }

  csect_exit (thread_p, CSECT_HEAP_CHNGUESS);

  return chn;
}

/*
 * heap_chnguess_clear () - Clear any cached information for given client
 *                        used when client is shutdown
 *   return:
 *   tran_index(in): The client transaction index
 *
 * Note: Clear the transaction index bit for all chnguess entries.
 */
void
heap_chnguess_clear (THREAD_ENTRY * thread_p, int tran_index)
{
  int i;
  HEAP_CHNGUESS_ENTRY *entry;

  if (csect_enter (thread_p, CSECT_HEAP_CHNGUESS, INF_WAIT) != NO_ERROR)
    {
      return;
    }

  if (heap_Guesschn != NULL)
    {
      for (i = 0; i < heap_Guesschn->num_entries; i++)
    {
      entry = &heap_Guesschn_area.entries[i];
      if (!OID_ISNULL (&entry->oid))
        {
          HEAP_BIT_CLEAR (entry->bits, (unsigned int) tran_index);
        }
    }
    }

  csect_exit (thread_p, CSECT_HEAP_CHNGUESS);

}

/*
 * Recovery functions
 */

/*
 * heap_rv_redo_newpage () - Redo the statistics or a new page allocation for
 *                           a heap file
 *   return: int
 *   rcv(in): Recovery structure
 */
int
heap_rv_redo_newpage (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  RECDES recdes;
  INT16 slotid;
  int sp_success;

  (void) pgbuf_set_page_ptype (thread_p, rcv->pgptr, PAGE_HEAP);

  /* Initialize header page */
  spage_initialize (thread_p, rcv->pgptr, heap_get_spage_type (), HEAP_MAX_ALIGN, SAFEGUARD_RVSPACE);

  /* Now insert first record (either statistics or chain record) */
  recdes.area_size = recdes.length = rcv->length;
  recdes.type = REC_HOME;
  recdes.data = (char *) rcv->data;
  sp_success = spage_insert (thread_p, rcv->pgptr, &recdes, &slotid);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  if (sp_success != SP_SUCCESS || slotid != HEAP_HEADER_AND_CHAIN_SLOTID)
    {
      if (sp_success != SP_SUCCESS)
    {
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
    }
      /* something went wrong. Unable to redo initialization of new heap page */
      assert (er_errid () != NO_ERROR);
      return er_errid ();
    }

  return NO_ERROR;
}

/*
 * heap_rv_undoredo_pagehdr () - Recover the header of a heap page
 *                    (either statistics/chain)
 *   return: int
 *   rcv(in): Recovery structure
 *
 * Note: Recover the update of the header or a heap page. The header
 * can be the heap header or a chain header.
 */
int
heap_rv_undoredo_pagehdr (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  RECDES recdes;
  int sp_success;

  (void) pgbuf_check_page_ptype (thread_p, rcv->pgptr, PAGE_HEAP);

  recdes.area_size = recdes.length = rcv->length;
  recdes.type = REC_HOME;
  recdes.data = (char *) rcv->data;

  sp_success = spage_update (thread_p, rcv->pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  if (sp_success != SP_SUCCESS)
    {
      /* something went wrong. Unable to redo update statistics for chain */
      if (sp_success != SP_ERROR)
    {
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
    }
      assert (er_errid () != NO_ERROR);
      return er_errid ();
    }
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return NO_ERROR;
}

/*
 * heap_rv_dump_statistics () - Dump statistics recovery information
 *   return: int
 *   ignore_length(in): Length of Recovery Data
 *   data(in): The data being logged
 *
 * Note: Dump statistics recovery information
 */
void
heap_rv_dump_statistics (FILE * fp, int ignore_length, void *data)
{
  int ret = NO_ERROR;

  HEAP_HDR_STATS *heap_hdr; /* Header of heap structure */

  heap_hdr = (HEAP_HDR_STATS *) data;
  ret = heap_dump_hdr (fp, heap_hdr);
}

/*
 * heap_rv_dump_chain () - Dump chain recovery information
 *   return: int
 *   ignore_length(in): Length of Recovery Data
 *   data(in): The data being logged
 */
void
heap_rv_dump_chain (FILE * fp, int ignore_length, void *data)
{
  HEAP_CHAIN *chain;

  chain = (HEAP_CHAIN *) data;
  fprintf (fp, "CLASS_OID = %2d|%4d|%2d, PREV_VPID = %2d|%4d, NEXT_VPID = %2d|%4d, MAX_MVCCID=%llu, flags=%d.\n",
       chain->class_oid.volid, chain->class_oid.pageid, chain->class_oid.slotid, chain->prev_vpid.volid,
       chain->prev_vpid.pageid, chain->next_vpid.volid, chain->next_vpid.pageid,
       (unsigned long long int) chain->max_mvccid, (int) chain->flags);
}

/*
 * heap_rv_redo_insert () - Redo the insertion of an object
 *   return: int
 *   rcv(in): Recovery structure
 *
 * Note: Redo the insertion of an object at a specific location (OID).
 */
int
heap_rv_redo_insert (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 slotid;
  RECDES recdes;
  int sp_success;

  slotid = rcv->offset;
  recdes.type = *(INT16 *) (rcv->data);
  recdes.data = (char *) (rcv->data) + sizeof (recdes.type);
  recdes.area_size = recdes.length = rcv->length - sizeof (recdes.type);

  if (recdes.type == REC_ASSIGN_ADDRESS)
    {
      /* 
       * The data here isn't really the data to be inserted (because there
       * wasn't any); instead it's the number of bytes that were reserved
       * for future insertion.  Change recdes.length to reflect the number
       * of bytes to reserve, but there's no need for a valid recdes.data:
       * spage_insert_for_recovery knows to ignore it in this case.
       */
      recdes.area_size = recdes.length = *(INT16 *) recdes.data;
      recdes.data = NULL;
    }

  sp_success = spage_insert_for_recovery (thread_p, rcv->pgptr, slotid, &recdes);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  if (sp_success != SP_SUCCESS)
    {
      /* Unable to redo insertion */
      if (sp_success != SP_ERROR)
    {
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
    }
      assert (er_errid () != NO_ERROR);
      return er_errid ();
    }

  return NO_ERROR;
}

/*
 * heap_mvcc_log_insert () - Log MVCC insert heap operation.
 *
 * return    : Void.
 * thread_p (in) : Thread entry.
 * p_recdes (in) : Newly inserted record.
 * p_addr (in)   : Log address data.
 */
static void
heap_mvcc_log_insert (THREAD_ENTRY * thread_p, RECDES * p_recdes, LOG_DATA_ADDR * p_addr)
{
#define HEAP_LOG_MVCC_INSERT_MAX_REDO_CRUMBS        4

  int n_redo_crumbs = 0, data_copy_offset = 0, chn_offset;
  LOG_CRUMB redo_crumbs[HEAP_LOG_MVCC_INSERT_MAX_REDO_CRUMBS];
  INT32 mvcc_flags;
  HEAP_PAGE_VACUUM_STATUS vacuum_status;

  assert (p_recdes != NULL);
  assert (p_addr != NULL);

  vacuum_status = heap_page_get_vacuum_status (thread_p, p_addr->pgptr);

  /* Update chain. */
  heap_page_update_chain_after_mvcc_op (thread_p, p_addr->pgptr, logtb_get_current_mvccid (thread_p));
  if (vacuum_status != heap_page_get_vacuum_status (thread_p, p_addr->pgptr))
    {
      /* Mark status change for recovery. */
      p_addr->offset |= HEAP_RV_FLAG_VACUUM_STATUS_CHANGE;
    }

  /* Build redo crumbs */
  /* Add record type */
  redo_crumbs[n_redo_crumbs].length = sizeof (p_recdes->type);
  redo_crumbs[n_redo_crumbs++].data = &p_recdes->type;

  if (p_recdes->type != REC_BIGONE)
    {
      mvcc_flags = (INT32) OR_GET_MVCC_FLAG (p_recdes->data);
      chn_offset = OR_CHN_OFFSET;

      /* Add representation ID and flags field */
      redo_crumbs[n_redo_crumbs].length = OR_INT_SIZE;
      redo_crumbs[n_redo_crumbs++].data = p_recdes->data;

      /* Add CHN */
      redo_crumbs[n_redo_crumbs].length = OR_INT_SIZE;
      redo_crumbs[n_redo_crumbs++].data = p_recdes->data + chn_offset;

      /* Set data copy offset after the record header */
      data_copy_offset = OR_HEADER_SIZE (p_recdes->data);
    }

  /* Add record data - record may be skipped if the record is not big one */
  redo_crumbs[n_redo_crumbs].length = p_recdes->length - data_copy_offset;
  redo_crumbs[n_redo_crumbs++].data = p_recdes->data + data_copy_offset;

  /* Safe guard */
  assert (n_redo_crumbs <= HEAP_LOG_MVCC_INSERT_MAX_REDO_CRUMBS);

  /* Append redo crumbs; undo crumbs not necessary as the spage_delete physical operation uses the offset field of the
   * address */
  log_append_undoredo_crumbs (thread_p, RVHF_MVCC_INSERT, p_addr, 0, n_redo_crumbs, NULL, redo_crumbs);
}

/*
 * heap_rv_mvcc_redo_insert () - Redo the MVCC insertion of an object
 *   return: int
 *   rcv(in): Recovery structure
 *
 * Note: MVCC redo the insertion of an object at a specific location (OID).
 */
int
heap_rv_mvcc_redo_insert (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 slotid;
  RECDES recdes;
  int chn, sp_success;
  MVCC_REC_HEADER mvcc_rec_header;
  INT16 record_type;
  bool vacuum_status_change = false;

  assert (rcv->pgptr != NULL);
  assert (MVCCID_IS_NORMAL (rcv->mvcc_id));

  slotid = rcv->offset;
  if (slotid & HEAP_RV_FLAG_VACUUM_STATUS_CHANGE)
    {
      vacuum_status_change = true;
    }
  slotid = slotid & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
  assert (slotid > 0);

  record_type = *(INT16 *) rcv->data;
  if (record_type == REC_BIGONE)
    {
      /* no data header */
      HEAP_SET_RECORD (&recdes, rcv->length - sizeof (record_type), rcv->length - sizeof (record_type), REC_BIGONE,
               rcv->data + sizeof (record_type));
    }
  else
    {
      char data_buffer[IO_DEFAULT_PAGE_SIZE + OR_MVCC_MAX_HEADER_SIZE + MAX_ALIGNMENT];
      int repid_and_flags, offset, mvcc_flag, offset_size;

      offset = sizeof (record_type);

      repid_and_flags = OR_GET_INT (rcv->data + offset);
      offset += OR_INT_SIZE;

      chn = OR_GET_INT (rcv->data + offset);
      offset += OR_INT_SIZE;

      mvcc_flag = (char) ((repid_and_flags >> OR_MVCC_FLAG_SHIFT_BITS) & OR_MVCC_FLAG_MASK);

      assert (!(mvcc_flag & OR_MVCC_FLAG_VALID_DELID));

      if ((repid_and_flags & OR_OFFSET_SIZE_FLAG) == OR_OFFSET_SIZE_1BYTE)
    {
      offset_size = OR_BYTE_SIZE;
    }
      else if ((repid_and_flags & OR_OFFSET_SIZE_FLAG) == OR_OFFSET_SIZE_2BYTE)
    {
      offset_size = OR_SHORT_SIZE;
    }
      else
    {
      offset_size = OR_INT_SIZE;
    }

      MVCC_SET_REPID (&mvcc_rec_header, repid_and_flags & OR_MVCC_REPID_MASK);
      MVCC_SET_FLAG (&mvcc_rec_header, mvcc_flag);
      MVCC_SET_INSID (&mvcc_rec_header, rcv->mvcc_id);
      MVCC_SET_CHN (&mvcc_rec_header, chn);

      HEAP_SET_RECORD (&recdes, IO_DEFAULT_PAGE_SIZE + OR_MVCC_MAX_HEADER_SIZE, 0, record_type,
               PTR_ALIGN (data_buffer, MAX_ALIGNMENT));
      or_mvcc_add_header (&recdes, &mvcc_rec_header, repid_and_flags & OR_BOUND_BIT_FLAG, offset_size);

      memcpy (recdes.data + recdes.length, rcv->data + offset, rcv->length - offset);
      recdes.length += (rcv->length - offset);
    }

  sp_success = spage_insert_for_recovery (thread_p, rcv->pgptr, slotid, &recdes);

  if (sp_success != SP_SUCCESS)
    {
      /* Unable to redo insertion */
      assert_release (false);
      return ER_FAILED;
    }

  heap_page_rv_chain_update (thread_p, rcv->pgptr, rcv->mvcc_id, vacuum_status_change);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return NO_ERROR;
}

/*
 * heap_rv_undo_insert () - Undo the insertion of an object.
 *   return: int
 *   rcv(in): Recovery structure
 *
 * Note: Delete an object for recovery purposes. The OID of the object
 * is reused since the object was never committed.
 */
int
heap_rv_undo_insert (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 slotid;

  slotid = rcv->offset;
  /* Clear HEAP_RV_FLAG_VACUUM_STATUS_CHANGE */
  slotid = slotid & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
  (void) spage_delete_for_recovery (thread_p, rcv->pgptr, slotid);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return NO_ERROR;
}

/*
 * heap_rv_redo_delete () - Redo the deletion of an object
 *   return: int
 *   rcv(in): Recovery structure
 *
 * Note: Redo the deletion of an object.
 * The OID of the object is not reuse since we don't know if the object was a
 * newly created object.
 */
int
heap_rv_redo_delete (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 slotid;

  slotid = rcv->offset;
  (void) spage_delete (thread_p, rcv->pgptr, slotid);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return NO_ERROR;
}

/*
 * heap_mvcc_log_delete () - Log normal MVCC heap delete operation (just
 *               append delete MVCCID and next version OID).
 *
 * return           : Void.
 * thread_p (in)        : Thread entry.
 * p_addr (in)          : Log address data.
 * rcvindex(in)         : Index to recovery function
 */
static void
heap_mvcc_log_delete (THREAD_ENTRY * thread_p, LOG_DATA_ADDR * p_addr, LOG_RCVINDEX rcvindex)
{
  char redo_data_buffer[OR_MVCCID_SIZE + MAX_ALIGNMENT];
  char *redo_data_p = PTR_ALIGN (redo_data_buffer, MAX_ALIGNMENT);
  char *ptr;
  int redo_data_size = 0;
  HEAP_PAGE_VACUUM_STATUS vacuum_status;

  assert (p_addr != NULL);
  assert (rcvindex == RVHF_MVCC_DELETE_REC_HOME || rcvindex == RVHF_MVCC_DELETE_REC_NEWHOME
      || rcvindex == RVHF_MVCC_DELETE_OVERFLOW);

  if (LOG_IS_MVCC_HEAP_OPERATION (rcvindex))
    {
      vacuum_status = heap_page_get_vacuum_status (thread_p, p_addr->pgptr);

      heap_page_update_chain_after_mvcc_op (thread_p, p_addr->pgptr, logtb_get_current_mvccid (thread_p));
      if (heap_page_get_vacuum_status (thread_p, p_addr->pgptr) != vacuum_status)
    {
      /* Mark vacuum status change for recovery. */
      p_addr->offset |= HEAP_RV_FLAG_VACUUM_STATUS_CHANGE;
    }
    }

  /* Prepare redo data. */
  ptr = redo_data_p;

  if (rcvindex != RVHF_MVCC_DELETE_REC_HOME)
    {
      /* MVCCID must be packed also, since it is not saved in log record structure. */
      ptr = or_pack_mvccid (ptr, logtb_get_current_mvccid (thread_p));
      redo_data_size += OR_MVCCID_SIZE;
    }

  assert ((ptr - redo_data_buffer) <= (int) sizeof (redo_data_buffer));

  /* Log append undo/redo crumbs */
  log_append_undoredo_data (thread_p, rcvindex, p_addr, 0, redo_data_size, NULL, redo_data_p);
}

/*
 * heap_rv_mvcc_undo_delete () - Undo the MVCC deletion of an object
 *   return: int
 *   rcv(in): Recovery structure
 */
int
heap_rv_mvcc_undo_delete (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 slotid;
  MVCC_REC_HEADER mvcc_rec_header;
  char data_buffer[IO_MAX_PAGE_SIZE + MAX_ALIGNMENT];
  RECDES rebuild_record;

  slotid = rcv->offset;
  slotid = slotid & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
  assert (slotid > 0);

  rebuild_record.data = PTR_ALIGN (data_buffer, MAX_ALIGNMENT);
  rebuild_record.area_size = DB_PAGESIZE;
  if (spage_get_record (thread_p, rcv->pgptr, slotid, &rebuild_record, COPY) != S_SUCCESS)
    {
      assert_release (false);
      return ER_FAILED;
    }
  assert (rebuild_record.type == REC_HOME || rebuild_record.type == REC_NEWHOME);

  if (or_mvcc_get_header (&rebuild_record, &mvcc_rec_header) != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }
  assert (MVCC_IS_FLAG_SET (&mvcc_rec_header, OR_MVCC_FLAG_VALID_DELID));
  MVCC_CLEAR_FLAG_BITS (&mvcc_rec_header, OR_MVCC_FLAG_VALID_DELID);

  if (or_mvcc_set_header (&rebuild_record, &mvcc_rec_header) != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }

  if (spage_update (thread_p, rcv->pgptr, slotid, &rebuild_record) != SP_SUCCESS)
    {
      assert_release (false);
      return ER_FAILED;
    }

  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);
  return NO_ERROR;
}

/*
 * heap_rv_mvcc_undo_delete_overflow () - Undo MVCC delete of an overflow
 *                    record.
 *
 * return    : Error code.
 * thread_p (in) : Thread entry.
 * rcv (in)  : Recovery data.
 */
int
heap_rv_mvcc_undo_delete_overflow (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  MVCC_REC_HEADER mvcc_header;

  if (heap_get_mvcc_rec_header_from_overflow (rcv->pgptr, &mvcc_header, NULL) != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }

  /* All flags should be set. Overflow header should be set to maximum size */
  assert (MVCC_IS_FLAG_SET (&mvcc_header, OR_MVCC_FLAG_VALID_DELID));
  assert (MVCC_IS_FLAG_SET (&mvcc_header, OR_MVCC_FLAG_VALID_PREV_VERSION));

  MVCC_SET_DELID (&mvcc_header, MVCCID_NULL);

  /* Change header. */
  if (heap_set_mvcc_rec_header_on_overflow (rcv->pgptr, &mvcc_header) != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }

  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);
  return NO_ERROR;
}

/*
 * heap_rv_mvcc_redo_delete_internal () - Internal function to be used by
 *                    heap_rv_mvcc_redo_delete_home and
 *                    heap_rv_mvcc_redo_delete_newhome.
 *
 * return         : Error code.
 * thread_p (in)      : Thread entry.
 * page (in)          : Heap page.
 * slotid (in)        : Recovered record slotid.
 * mvccid (in)        : Delete MVCCID.
 */
static int
heap_rv_mvcc_redo_delete_internal (THREAD_ENTRY * thread_p, PAGE_PTR page, PGSLOTID slotid, MVCCID mvccid)
{
  RECDES rebuild_record;
  char data_buffer[IO_MAX_PAGE_SIZE + MAX_ALIGNMENT];
  MVCC_REC_HEADER mvcc_rec_header;

  assert (page != NULL);
  assert (MVCCID_IS_NORMAL (mvccid));

  rebuild_record.data = PTR_ALIGN (data_buffer, MAX_ALIGNMENT);
  rebuild_record.area_size = DB_PAGESIZE;

  /* Get record. */
  if (spage_get_record (thread_p, page, slotid, &rebuild_record, COPY) != S_SUCCESS)
    {
      assert_release (false);
      return ER_FAILED;
    }

  /* Get MVCC header. */
  if (or_mvcc_get_header (&rebuild_record, &mvcc_rec_header) != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }

  /* Set delete MVCCID. */
  MVCC_SET_FLAG_BITS (&mvcc_rec_header, OR_MVCC_FLAG_VALID_DELID);
  MVCC_SET_DELID (&mvcc_rec_header, mvccid);

  /* Change header. */
  if (or_mvcc_set_header (&rebuild_record, &mvcc_rec_header) != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }

  /* Update record in page. */
  if (spage_update (thread_p, page, slotid, &rebuild_record) != SP_SUCCESS)
    {
      assert_release (false);
      return ER_FAILED;
    }

  /* Success. */
  return NO_ERROR;
}

/*
 * heap_rv_mvcc_redo_delete_home () - Redo MVCC delete of REC_HOME record.
 *
 * return    : Error code
 * thread_p (in) : Thread entry.
 * rcv (in)  : Recovery data.
 */
int
heap_rv_mvcc_redo_delete_home (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  int error_code = NO_ERROR;
  int offset = 0;
  PGSLOTID slotid;
  bool vacuum_status_change = false;

  assert (rcv->pgptr != NULL);
  assert (MVCCID_IS_NORMAL (rcv->mvcc_id));

  slotid = rcv->offset;
  if (slotid & HEAP_RV_FLAG_VACUUM_STATUS_CHANGE)
    {
      vacuum_status_change = true;
    }
  slotid = slotid & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
  assert (slotid > 0);

  assert (offset == rcv->length);

  error_code = heap_rv_mvcc_redo_delete_internal (thread_p, rcv->pgptr, slotid, rcv->mvcc_id);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }
  heap_page_rv_chain_update (thread_p, rcv->pgptr, rcv->mvcc_id, vacuum_status_change);

  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);
  return NO_ERROR;
}

/*
 * heap_rv_mvcc_redo_delete_overflow () - Redo MVCC delete of overflow record.
 *
 * return    : Error code
 * thread_p (in) : Thread entry.
 * rcv (in)  : Recovery data.
 */
int
heap_rv_mvcc_redo_delete_overflow (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  int offset = 0;
  MVCCID mvccid;
  MVCC_REC_HEADER mvcc_header;

  assert (rcv->pgptr != NULL);

  OR_GET_MVCCID (rcv->data + offset, &mvccid);
  offset += OR_MVCCID_SIZE;

  assert (offset == rcv->length);

  if (heap_get_mvcc_rec_header_from_overflow (rcv->pgptr, &mvcc_header, NULL) != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }
  assert (MVCC_IS_FLAG_SET (&mvcc_header, OR_MVCC_FLAG_VALID_INSID));

  assert (MVCC_IS_FLAG_SET (&mvcc_header, OR_MVCC_FLAG_VALID_DELID));
  MVCC_SET_DELID (&mvcc_header, mvccid);

  /* Update MVCC header. */
  if (heap_set_mvcc_rec_header_on_overflow (rcv->pgptr, &mvcc_header) != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }

  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);
  return NO_ERROR;
}

/*
 * heap_rv_mvcc_redo_delete_newhome () - Redo MVCC delete of REC_NEWHOME
 *                   record.
 *
 * return    : Error code
 * thread_p (in) : Thread entry.
 * rcv (in)  : Recovery data.
 */
int
heap_rv_mvcc_redo_delete_newhome (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  int error_code = NO_ERROR;
  int offset = 0;
  MVCCID mvccid;

  assert (rcv->pgptr != NULL);

  OR_GET_MVCCID (rcv->data + offset, &mvccid);
  offset += OR_MVCCID_SIZE;


  assert (offset == rcv->length);

  error_code = heap_rv_mvcc_redo_delete_internal (thread_p, rcv->pgptr, rcv->offset, mvccid);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }

  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);
  return NO_ERROR;
}

/*
 * heap_rv_redo_mark_reusable_slot () - Marks a deleted slot as reusable; used
 *                                      as a postponed log operation and a
 *                                      REDO function
 *   return: int
 *   rcv(in): Recovery structure
 *
 * Note: Mark (during postponed operation execution)/Redo (during recovery)
 *       the marking of a deleted slot as reusable.
 */
int
heap_rv_redo_mark_reusable_slot (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 slotid;

  slotid = rcv->offset;
  (void) spage_mark_deleted_slot_as_reusable (thread_p, rcv->pgptr, slotid);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return NO_ERROR;
}

/*
 * heap_rv_undo_delete () - Undo the deletion of an object
 *   return: int
 *   rcv(in): Recovery structure
 */
int
heap_rv_undo_delete (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 slotid;
  INT16 recdes_type;
  int error_code;

  error_code = heap_rv_redo_insert (thread_p, rcv);
  if (error_code != NO_ERROR)
    {
      return error_code;
    }

  /* vacuum atomicity */
  recdes_type = *(INT16 *) (rcv->data);
  if (recdes_type == REC_NEWHOME)
    {
      slotid = rcv->offset;
      slotid = slotid & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
      error_code = vacuum_rv_check_at_undo (thread_p, rcv->pgptr, slotid, recdes_type);
      if (error_code != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }
    }

  return NO_ERROR;
}

/* 
 * heap_rv_undo_update () - Undo the update of an object 
 *   return: int
 *   rev(in): Recovery structure
 */
int
heap_rv_undo_update (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 recdes_type;
  int error_code;

  error_code = heap_rv_undoredo_update (thread_p, rcv);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }

  /* vacuum atomicity */
  recdes_type = *(INT16 *) (rcv->data);
  if (recdes_type == REC_HOME || recdes_type == REC_NEWHOME)
    {
      INT16 slotid;

      slotid = rcv->offset;
      slotid = slotid & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
      error_code = vacuum_rv_check_at_undo (thread_p, rcv->pgptr, slotid, recdes_type);
      if (error_code != NO_ERROR)
    {
      assert_release (false);
      return error_code;
    }
    }

  return NO_ERROR;
}

/* 
 * heap_rv_redo_update () - Redo the update of an object 
 *   return: int
 *   rcv(in): Recovrery structure
 */
int
heap_rv_redo_update (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  return heap_rv_undoredo_update (thread_p, rcv);
}

/*
 * heap_rv_undoredo_update () - Recover an update either for undo or redo
 *   return: int
 *   rcv(in): Recovery structure
 */
int
heap_rv_undoredo_update (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 slotid;
  RECDES recdes;
  int sp_success;

  slotid = rcv->offset;
  slotid = slotid & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
  assert (slotid > 0);

  recdes.type = *(INT16 *) (rcv->data);
  recdes.data = (char *) (rcv->data) + sizeof (recdes.type);
  recdes.area_size = recdes.length = rcv->length - sizeof (recdes.type);
  if (recdes.area_size <= 0)
    {
      sp_success = SP_SUCCESS;
    }
  else
    {
      if (heap_update_physical (thread_p, rcv->pgptr, slotid, &recdes) != NO_ERROR)
    {
      assert_release (false);
      return ER_FAILED;
    }
    }

  return NO_ERROR;
}

/*
 * heap_rv_redo_reuse_page () - Redo the deletion of all objects in page for
 *                              reuse purposes
 *   return: int
 *   rcv(in): Recovery structure
 */
int
heap_rv_redo_reuse_page (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  VPID vpid;
  RECDES recdes;
  HEAP_CHAIN *chain;        /* Chain to next and prev page */
  int sp_success;
  const bool is_header_page = ((rcv->offset != 0) ? true : false);

  (void) pgbuf_check_page_ptype (thread_p, rcv->pgptr, PAGE_HEAP);

  vpid.volid = pgbuf_get_volume_id (rcv->pgptr);
  vpid.pageid = pgbuf_get_page_id (rcv->pgptr);

  /* We ignore the return value. It should be true (objects were deleted) except for the scenario when the redo actions 
   * are applied twice. */
  (void) heap_delete_all_page_records (thread_p, &vpid, rcv->pgptr);

  /* At here, do not consider the header of heap. Later redo the update of the header of heap at RVHF_STATS log. */
  if (!is_header_page)
    {
      sp_success = spage_get_record (thread_p, rcv->pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK);
      if (sp_success != SP_SUCCESS)
    {
      /* something went wrong. Unable to redo update class_oid */
      if (sp_success != SP_ERROR)
        {
          er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
        }
      assert (er_errid () != NO_ERROR);
      return er_errid ();
    }

      chain = (HEAP_CHAIN *) recdes.data;
      COPY_OID (&(chain->class_oid), (OID *) (rcv->data));
      chain->max_mvccid = MVCCID_NULL;
      chain->flags = 0;
      HEAP_PAGE_SET_VACUUM_STATUS (chain, HEAP_PAGE_VACUUM_NONE);
    }

  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return NO_ERROR;
}

/*
 * heap_rv_redo_reuse_page_reuse_oid () - Redo the deletion of all objects in
 *                                        a reusable oid heap page for reuse
 *                                        purposes
 *   return: int
 *   rcv(in): Recovery structure
 */
int
heap_rv_redo_reuse_page_reuse_oid (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  RECDES recdes;
  HEAP_CHAIN *chain;        /* Chain to next and prev page */
  int sp_success;
  const bool is_header_page = ((rcv->offset != 0) ? true : false);

  (void) heap_reinitialize_page (thread_p, rcv->pgptr, is_header_page);

  (void) pgbuf_set_page_ptype (thread_p, rcv->pgptr, PAGE_HEAP);

  /* At here, do not consider the header of heap. Later redo the update of the header of heap at RVHF_STATS log. */
  if (!is_header_page)
    {
      sp_success = spage_get_record (thread_p, rcv->pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK);
      if (sp_success != SP_SUCCESS)
    {
      /* something went wrong. Unable to redo update class_oid */
      if (sp_success != SP_ERROR)
        {
          er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
        }
      assert (er_errid () != NO_ERROR);
      return er_errid ();
    }

      chain = (HEAP_CHAIN *) recdes.data;
      COPY_OID (&(chain->class_oid), (OID *) (rcv->data));
      chain->max_mvccid = MVCCID_NULL;
      chain->flags = 0;
      HEAP_PAGE_SET_VACUUM_STATUS (chain, HEAP_PAGE_VACUUM_NONE);
    }

  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return NO_ERROR;
}

/*
 * heap_rv_dump_reuse_page () - Dump reuse page
 *   return: int
 *   ignore_length(in): Length of Recovery Data
 *   ignore_data(in): The data being logged
 *
 * Note: Dump information about reuse of page.
 */
void
heap_rv_dump_reuse_page (FILE * fp, int ignore_length, void *ignore_data)
{
  fprintf (fp, "Delete all objects in page for reuse purposes of page\n");
}

/*
 * xheap_get_class_num_objects_pages () -
 *   return: NO_ERROR
 *   hfid(in):
 *   approximation(in):
 *   nobjs(in):
 *   npages(in):
 */
int
xheap_get_class_num_objects_pages (THREAD_ENTRY * thread_p, const HFID * hfid, int approximation, int *nobjs,
                   int *npages)
{
  int length, num;
  int ret;

  assert (!HFID_IS_NULL (hfid));

  if (approximation)
    {
      num = heap_estimate (thread_p, hfid, npages, nobjs, &length);
    }
  else
    {
      num = heap_get_num_objects (thread_p, hfid, npages, nobjs, &length);
    }

  if (num < 0)
    {
      return (((ret = er_errid ()) == NO_ERROR) ? ER_FAILED : ret);
    }

  return NO_ERROR;
}

/*
 * xheap_has_instance () -
 *   return:
 *   hfid(in):
 *   class_oid(in):
 *   has_visible_instance(in): true if we need to check for a visible record
 */
int
xheap_has_instance (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, int has_visible_instance)
{
  OID oid;
  HEAP_SCANCACHE scan_cache;
  RECDES recdes;
  SCAN_CODE r;
  MVCC_SNAPSHOT *mvcc_snapshot = NULL;

  OID_SET_NULL (&oid);

  if (has_visible_instance)
    {
      mvcc_snapshot = logtb_get_mvcc_snapshot (thread_p);
      if (mvcc_snapshot == NULL)
    {
      return ER_FAILED;
    }
    }
  if (heap_scancache_start (thread_p, &scan_cache, hfid, class_oid, true, false, mvcc_snapshot) != NO_ERROR)
    {
      return ER_FAILED;
    }

  recdes.data = NULL;
  r = heap_first (thread_p, hfid, class_oid, &oid, &recdes, &scan_cache, true);
  heap_scancache_end (thread_p, &scan_cache);

  if (r == S_ERROR)
    {
      return ER_FAILED;
    }
  else if (r == S_DOESNT_EXIST || r == S_END)
    {
      return 0;
    }
  else
    {
      return 1;
    }
}

/*
 * heap_get_class_repr_id () -
 *   return:
 *   class_oid(in):
 */
REPR_ID
heap_get_class_repr_id (THREAD_ENTRY * thread_p, OID * class_oid)
{
  OR_CLASSREP *rep = NULL;
  REPR_ID id;
  int idx_incache = -1;

  if (!class_oid || !idx_incache)
    {
      return 0;
    }

  rep = heap_classrepr_get (thread_p, class_oid, NULL, NULL_REPRID, &idx_incache);
  if (rep == NULL)
    {
      return 0;
    }

  id = rep->id;
  heap_classrepr_free_and_init (rep, &idx_incache);

  return id;
}

/*
 * heap_set_autoincrement_value () -
 *   return: NO_ERROR, or ER_code
 *   attr_info(in):
 *   scan_cache(in):
 *   is_set(out): 1 if at least one autoincrement value has been set
 */
int
heap_set_autoincrement_value (THREAD_ENTRY * thread_p, HEAP_CACHE_ATTRINFO * attr_info, HEAP_SCANCACHE * scan_cache,
                  int *is_set)
{
  int i, idx_in_cache;
  char *classname = NULL;
  char *attr_name = NULL;
  RECDES recdes;        /* Used to obtain attribute name */
  char serial_name[AUTO_INCREMENT_SERIAL_NAME_MAX_LENGTH];
  HEAP_ATTRVALUE *value;
  DB_VALUE dbvalue_numeric, *dbvalue, key_val;
  OR_ATTRIBUTE *att;
  OID serial_class_oid;
  LC_FIND_CLASSNAME status;
  OR_CLASSREP *classrep;
  BTID serial_btid;
  DB_DATA_STATUS data_stat;
  HEAP_SCANCACHE local_scan_cache;
  bool use_local_scan_cache = false;
  int ret = NO_ERROR;
  int alloced_string = 0;
  char *string = NULL;

  if (!attr_info || !scan_cache)
    {
      return ER_FAILED;
    }

  *is_set = 0;

  recdes.data = NULL;
  recdes.area_size = 0;

  for (i = 0; i < attr_info->num_values; i++)
    {
      value = &attr_info->values[i];
      dbvalue = &value->dbvalue;
      att = &attr_info->last_classrepr->attributes[i];

      if (att->is_autoincrement && (value->state == HEAP_UNINIT_ATTRVALUE))
    {
      if (OID_ISNULL (&(att->auto_increment.serial_obj)))
        {
          memset (serial_name, '\0', sizeof (serial_name));
          recdes.data = NULL;
          recdes.area_size = 0;

          if (scan_cache->cache_last_fix_page == false)
        {
          scan_cache = &local_scan_cache;
          (void) heap_scancache_quick_start_root_hfid (thread_p, scan_cache);
          use_local_scan_cache = true;
        }

          if (heap_get_class_record (thread_p, &(attr_info->class_oid), &recdes, scan_cache, PEEK) != S_SUCCESS)
        {
          ret = ER_FAILED;
          goto exit_on_error;
        }

          if (heap_get_class_name (thread_p, &(att->classoid), &classname) != NO_ERROR || classname == NULL)
        {
          ASSERT_ERROR_AND_SET (ret);
          goto exit_on_error;
        }

          string = NULL;
          alloced_string = 0;

          ret = or_get_attrname (&recdes, att->id, &string, &alloced_string);
          if (ret != NO_ERROR)
        {
          ASSERT_ERROR ();
          goto exit_on_error;
        }

          attr_name = string;
          if (attr_name == NULL)
        {
          ret = ER_FAILED;
          goto exit_on_error;
        }

          SET_AUTO_INCREMENT_SERIAL_NAME (serial_name, classname, attr_name);

          if (string != NULL && alloced_string == 1)
        {
          db_private_free_and_init (thread_p, string);
        }

          free_and_init (classname);

          if (db_make_varchar (&key_val, DB_MAX_IDENTIFIER_LENGTH, serial_name, (int) strlen (serial_name),
                   LANG_SYS_CODESET, LANG_SYS_COLLATION) != NO_ERROR)
        {
          ret = ER_FAILED;
          goto exit_on_error;
        }

          status = xlocator_find_class_oid (thread_p, CT_SERIAL_NAME, &serial_class_oid, NULL_LOCK);
          if (status == LC_CLASSNAME_ERROR || status == LC_CLASSNAME_DELETED)
        {
          ret = ER_FAILED;
          goto exit_on_error;
        }

          classrep = heap_classrepr_get (thread_p, &serial_class_oid, NULL, NULL_REPRID, &idx_in_cache);
          if (classrep == NULL)
        {
          ret = ER_FAILED;
          goto exit_on_error;
        }

          if (classrep->indexes)
        {
          BTREE_SEARCH search_result;
          OID serial_oid;

          BTID_COPY (&serial_btid, &(classrep->indexes[0].btid));
          search_result =
            xbtree_find_unique (thread_p, &serial_btid, S_SELECT, &key_val, &serial_class_oid, &serial_oid,
                    false);
          heap_classrepr_free_and_init (classrep, &idx_in_cache);
          if (search_result != BTREE_KEY_FOUND)
            {
              ret = ER_FAILED;
              goto exit_on_error;
            }

          assert (!OID_ISNULL (&serial_oid));
          ATOMIC_CAS_64 ((INT64 *) (&att->auto_increment.serial_obj), *(INT64 *) (&oid_Null_oid),
                 *(INT64 *) (&serial_oid));
        }
          else
        {
          heap_classrepr_free_and_init (classrep, &idx_in_cache);
          ret = ER_FAILED;
          goto exit_on_error;
        }
        }

      if ((att->type == DB_TYPE_SHORT) || (att->type == DB_TYPE_INTEGER) || (att->type == DB_TYPE_BIGINT))
        {
          if (xserial_get_next_value (thread_p, &dbvalue_numeric, &att->auto_increment.serial_obj, 0,   /* no cache */
                      1,    /* generate one value */
                      GENERATE_AUTO_INCREMENT, false) != NO_ERROR)
        {
          ret = ER_FAILED;
          goto exit_on_error;
        }

          if (numeric_db_value_coerce_from_num (&dbvalue_numeric, dbvalue, &data_stat) != NO_ERROR)
        {
          ret = ER_FAILED;
          goto exit_on_error;
        }
        }
      else if (att->type == DB_TYPE_NUMERIC)
        {
          if (xserial_get_next_value (thread_p, dbvalue, &att->auto_increment.serial_obj, 0,    /* no cache */
                      1,    /* generate one value */
                      GENERATE_AUTO_INCREMENT, false) != NO_ERROR)
        {
          ret = ER_FAILED;
          goto exit_on_error;
        }
        }

      *is_set = 1;
      value->state = HEAP_READ_ATTRVALUE;
    }
    }

  if (use_local_scan_cache)
    {
      heap_scancache_end (thread_p, scan_cache);
    }

  return ret;

exit_on_error:
  if (classname != NULL)
    {
      free_and_init (classname);
    }

  if (use_local_scan_cache)
    {
      heap_scancache_end (thread_p, scan_cache);
    }
  return ret;
}

/*
 * heap_attrinfo_set_uninitialized_global () -
 *   return: NO_ERROR
 *   inst_oid(in):
 *   recdes(in):
 *   attr_info(in):
 */
int
heap_attrinfo_set_uninitialized_global (THREAD_ENTRY * thread_p, OID * inst_oid, RECDES * recdes,
                    HEAP_CACHE_ATTRINFO * attr_info)
{
  if (attr_info == NULL)
    {
      return ER_FAILED;
    }

  return heap_attrinfo_set_uninitialized (thread_p, inst_oid, recdes, attr_info);
}

/*
 * heap_get_hfid_from_class_oid () - get HFID from class oid
 *   return: error_code
 *   class_oid(in): class oid
 *   hfid(out):  the resulting hfid
 */
int
heap_get_hfid_from_class_oid (THREAD_ENTRY * thread_p, const OID * class_oid, HFID * hfid)
{
  int error_code = NO_ERROR;

  error_code = heap_hfid_cache_get (thread_p, class_oid, hfid, NULL);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }

  return error_code;
}

/*
 * heap_get_hfid_and_file_type_from_class_oid () - get HFID and file type for class.
 *
 * return          : error code
 * thread_p (in)   : thread entry
 * class_oid (in)  : class OID
 * hfid_out (out)  : output heap file identifier
 * ftype_out (out) : output heap file type
 */
int
heap_get_hfid_and_file_type_from_class_oid (THREAD_ENTRY * thread_p, const OID * class_oid, HFID * hfid_out,
                        FILE_TYPE * ftype_out)
{
  int error_code = NO_ERROR;

  error_code = heap_hfid_cache_get (thread_p, class_oid, hfid_out, ftype_out);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR_AND_SET (error_code);
      return error_code;
    }

  return error_code;
}

/*
 * heap_compact_pages () - compact all pages from hfid of specified class OID
 *   return: error_code
 *   class_oid(out):  the class oid
 */
int
heap_compact_pages (THREAD_ENTRY * thread_p, OID * class_oid)
{
  int ret = NO_ERROR;
  VPID vpid;
  VPID next_vpid;
  LOG_DATA_ADDR addr;
  HFID hfid;
  PGBUF_WATCHER pg_watcher;
  PGBUF_WATCHER old_pg_watcher;

  if (class_oid == NULL)
    {
      return ER_QPROC_INVALID_PARAMETER;
    }

  if (lock_object (thread_p, class_oid, oid_Root_class_oid, IS_LOCK, LK_UNCOND_LOCK) != LK_GRANTED)
    {
      return ER_FAILED;
    }

  ret = heap_get_hfid_from_class_oid (thread_p, class_oid, &hfid);
  if (ret != NO_ERROR || HFID_IS_NULL (&hfid))
    {
      lock_unlock_object (thread_p, class_oid, oid_Root_class_oid, IS_LOCK, true);
      return ret;
    }

  PGBUF_INIT_WATCHER (&pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, &hfid);
  PGBUF_INIT_WATCHER (&old_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, &hfid);

  addr.vfid = &hfid.vfid;
  addr.pgptr = NULL;
  addr.offset = 0;

  vpid.volid = hfid.vfid.volid;
  vpid.pageid = hfid.hpgid;

  if (pgbuf_ordered_fix (thread_p, &vpid, OLD_PAGE, PGBUF_LATCH_READ, &pg_watcher) != NO_ERROR)
    {
      lock_unlock_object (thread_p, class_oid, oid_Root_class_oid, IS_LOCK, true);
      ret = ER_FAILED;
      goto exit_on_error;
    }

  (void) pgbuf_check_page_ptype (thread_p, pg_watcher.pgptr, PAGE_HEAP);

  lock_unlock_object (thread_p, class_oid, oid_Root_class_oid, IS_LOCK, true);

  /* skip header page */
  ret = heap_vpid_next (thread_p, &hfid, pg_watcher.pgptr, &next_vpid);
  if (ret != NO_ERROR)
    {
      goto exit_on_error;
    }
  pgbuf_replace_watcher (thread_p, &pg_watcher, &old_pg_watcher);

  while (!VPID_ISNULL (&next_vpid))
    {
      vpid = next_vpid;
      pg_watcher.pgptr =
    heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE_PREVENT_DEALLOC, X_LOCK, NULL, &pg_watcher);
      if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }
      if (pg_watcher.pgptr == NULL)
    {
      ret = ER_FAILED;
      goto exit_on_error;
    }

      ret = heap_vpid_next (thread_p, &hfid, pg_watcher.pgptr, &next_vpid);
      if (ret != NO_ERROR)
    {
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
      goto exit_on_error;
    }

      if (spage_compact (thread_p, pg_watcher.pgptr) != NO_ERROR)
    {
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
      ret = ER_FAILED;
      goto exit_on_error;
    }

      addr.pgptr = pg_watcher.pgptr;
      log_skip_logging (thread_p, &addr);
      pgbuf_set_dirty (thread_p, pg_watcher.pgptr, DONT_FREE);
      pgbuf_replace_watcher (thread_p, &pg_watcher, &old_pg_watcher);
    }

  if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }
  assert (pg_watcher.pgptr == NULL);

  return ret;

exit_on_error:

  if (pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
    }
  if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }

  return ret;
}

/*
 * heap_classrepr_dump_all () - dump all representations belongs to a class
 *   return: none
 *   fp(in): file pointer to print out
 *   class_oid(in): class oid to be dumped
 */
void
heap_classrepr_dump_all (THREAD_ENTRY * thread_p, FILE * fp, OID * class_oid)
{
  RECDES peek_recdes;
  HEAP_SCANCACHE scan_cache;
  OR_CLASSREP **rep_all;
  int count, i;
  char *classname;
  bool need_free_classname = false;

  if (heap_get_class_name (thread_p, class_oid, &classname) != NO_ERROR || classname == NULL)
    {
      classname = (char *) "unknown";
      er_clear ();
    }
  else
    {
      need_free_classname = true;
    }

  heap_scancache_quick_start_root_hfid (thread_p, &scan_cache);

  if (heap_get_class_record (thread_p, class_oid, &peek_recdes, &scan_cache, PEEK) == S_SUCCESS)
    {
      rep_all = or_get_all_representation (&peek_recdes, true, &count);
      fprintf (fp, "*** Dumping representations of class %s\n    Classname = %s, Class-OID = %d|%d|%d, #Repr = %d\n",
           classname, classname, (int) class_oid->volid, class_oid->pageid, (int) class_oid->slotid, count);

      for (i = 0; i < count; i++)
    {
      assert (rep_all[i] != NULL);
      heap_classrepr_dump (thread_p, fp, class_oid, rep_all[i]);
      or_free_classrep (rep_all[i]);
    }

      fprintf (fp, "\n*** End of dump.\n");
      free_and_init (rep_all);
    }

  heap_scancache_end (thread_p, &scan_cache);

  if (need_free_classname)
    {
      free_and_init (classname);
    }
}

/*
 * heap_get_btid_from_index_name () - gets the BTID of an index using its name
 *                    and OID of class
 *
 *   return: NO_ERROR, or error code
 *   thread_p(in)   : thread context
 *   p_class_oid(in): OID of class
 *   index_name(in) : name of index
 *   p_found_btid(out): the BTREE ID of index
 *
 *  Note : the 'p_found_btid' argument must be a pointer to a BTID value,
 *     the found BTID is 'BTID_COPY-ed' into it.
 *     Null arguments are not allowed.
 *     If an index name is not found, the 'p_found_btid' is returned as
 *     NULL BTID and no error is set.
 *
 */
int
heap_get_btid_from_index_name (THREAD_ENTRY * thread_p, const OID * p_class_oid, const char *index_name,
                   BTID * p_found_btid)
{
  int error = NO_ERROR;
  int classrepr_cacheindex = -1;
  int idx_cnt;
  OR_CLASSREP *classrepr = NULL;
  OR_INDEX *curr_index = NULL;

  assert (p_found_btid != NULL);
  assert (p_class_oid != NULL);
  assert (index_name != NULL);

  BTID_SET_NULL (p_found_btid);

  /* get the BTID associated from the index name : the only structure containing this info is OR_CLASSREP */

  /* get class representation */
  classrepr = heap_classrepr_get (thread_p, (OID *) p_class_oid, NULL, NULL_REPRID, &classrepr_cacheindex);

  if (classrepr == NULL)
    {
      error = er_errid ();
      if (error == NO_ERROR)
    {
      assert (error != NO_ERROR);
      error = ER_FAILED;
    }
      goto exit;
    }

  /* iterate through indexes looking for index name */
  for (idx_cnt = 0, curr_index = classrepr->indexes; idx_cnt < classrepr->n_indexes; idx_cnt++, curr_index++)
    {
      if (curr_index == NULL)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_UNEXPECTED, 1, "Bad index information in class representation.");
      error = ER_UNEXPECTED;
      goto exit_cleanup;
    }

      if (intl_identifier_casecmp (curr_index->btname, index_name) == 0)
    {
      BTID_COPY (p_found_btid, &(curr_index->btid));
      break;
    }
    }

exit_cleanup:
  if (classrepr)
    {
      heap_classrepr_free_and_init (classrepr, &classrepr_cacheindex);
    }

exit:
  return error;
}

/*
 * heap_object_upgrade_domain - upgrades a single attibute in an instance from
 *              the domain of current representation to the
 *              domain of the last representation.
 *
 *    return: error code , NO_ERROR if no error occured
 *    thread_p(in) : thread context
 *    upd_scancache(in): scan context
 *    attr_info(in): aatribute info structure
 *    oid(in): the oid of the object to process
 *    att_id(in): attribute id within the class (same as in schema)
 *
 *  Note : this function is used in ALTER CHANGE (with type change syntax)
 */
int
heap_object_upgrade_domain (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * upd_scancache, HEAP_CACHE_ATTRINFO * attr_info,
                OID * oid, const ATTR_ID att_id)
{
  int i = 0, error = NO_ERROR;
  HEAP_ATTRVALUE *value = NULL;
  int force_count = 0, updated_n_attrs_id = 0;
  ATTR_ID atts_id[1] = { 0 };
  DB_VALUE orig_value;

  db_make_null (&orig_value);

  if (upd_scancache == NULL || attr_info == NULL || oid == NULL)
    {
      error = ER_UNEXPECTED;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, error, 1, "Unexpected NULL arguments.");
      goto exit;
    }

  for (i = 0, value = attr_info->values; i < attr_info->num_values; i++, value++)
    {
      TP_DOMAIN *dest_dom = value->last_attrepr->domain;
      bool log_warning = false;
      int warning_code = NO_ERROR;
      DB_TYPE dest_type;
      DB_TYPE src_type = DB_VALUE_DOMAIN_TYPE (&(value->dbvalue));
      int curr_prec = 0;
      int dest_prec = 0;

      dest_type = TP_DOMAIN_TYPE (dest_dom);

      if (att_id != value->attrid)
    {
      continue;
    }

      if (QSTR_IS_BIT (src_type))
    {
      curr_prec = db_get_string_length (&(value->dbvalue));
    }
      else if (QSTR_IS_ANY_CHAR (src_type))
    {
      if (TP_DOMAIN_CODESET (dest_dom) == INTL_CODESET_RAW_BYTES)
        {
          curr_prec = db_get_string_size (&(value->dbvalue));
        }
      else if (!DB_IS_NULL (&(value->dbvalue)))
        {
          curr_prec = db_get_string_length (&(value->dbvalue));
        }
      else
        {
          curr_prec = dest_dom->precision;
        }
    }

      dest_prec = dest_dom->precision;

      if (QSTR_IS_ANY_CHAR_OR_BIT (src_type) && QSTR_IS_ANY_CHAR_OR_BIT (dest_type))
    {
      /* check phase of ALTER TABLE .. CHANGE should not allow changing the domains from one flavour to another : */
      assert ((QSTR_IS_CHAR (src_type) && QSTR_IS_CHAR (dest_type))
          || (!QSTR_IS_CHAR (src_type) && !QSTR_IS_CHAR (dest_type)));

      assert ((QSTR_IS_NATIONAL_CHAR (src_type) && QSTR_IS_NATIONAL_CHAR (dest_type))
          || (!QSTR_IS_NATIONAL_CHAR (src_type) && !QSTR_IS_NATIONAL_CHAR (dest_type)));

      assert ((QSTR_IS_BIT (src_type) && QSTR_IS_BIT (dest_type))
          || (!QSTR_IS_BIT (src_type) && !QSTR_IS_BIT (dest_type)));

      /* check string truncation */
      if (dest_prec < curr_prec)
        {
          if (prm_get_bool_value (PRM_ID_ALTER_TABLE_CHANGE_TYPE_STRICT) == true)
        {
          error = ER_ALTER_CHANGE_TRUNC_OVERFLOW_NOT_ALLOWED;
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, error, 0);
          goto exit;
        }
          else
        {
          /* allow truncation in cast, just warning */
          log_warning = true;
          warning_code = ER_QPROC_SIZE_STRING_TRUNCATED;
        }
        }
    }

      error = pr_clone_value (&(value->dbvalue), &orig_value);
      if (error != NO_ERROR)
    {
      goto exit;
    }

      if (TP_IS_CHAR_TYPE (TP_DOMAIN_TYPE (dest_dom))
      && !(TP_IS_CHAR_TYPE (src_type) || src_type == DB_TYPE_ENUMERATION)
      && prm_get_bool_value (PRM_ID_ALTER_TABLE_CHANGE_TYPE_STRICT) == false)
    {
      /* If destination is char/varchar, we need to first cast the value to a string with no precision, then to
       * destination type with the desired precision. */
      TP_DOMAIN *string_dom;
      if (TP_DOMAIN_TYPE (dest_dom) == DB_TYPE_NCHAR || TP_DOMAIN_TYPE (dest_dom) == DB_TYPE_VARNCHAR)
        {
          string_dom = tp_domain_resolve_default (DB_TYPE_VARNCHAR);
        }
      else
        {
          string_dom = tp_domain_resolve_default (DB_TYPE_VARCHAR);
        }
      error = db_value_coerce (&(value->dbvalue), &(value->dbvalue), string_dom);
    }

      if (error == NO_ERROR)
    {
      error = db_value_coerce (&(value->dbvalue), &(value->dbvalue), dest_dom);
    }
      if (error != NO_ERROR)
    {
      bool set_default_value = false;
      bool set_min_value = false;
      bool set_max_value = false;

      if (prm_get_bool_value (PRM_ID_ALTER_TABLE_CHANGE_TYPE_STRICT) == true)
        {
          error = ER_ALTER_CHANGE_TRUNC_OVERFLOW_NOT_ALLOWED;
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, error, 0);
          goto exit;
        }

      if (error == ER_IT_DATA_OVERFLOW)
        {
          int is_positive = -1; /* -1:UNKNOWN, 0:negative, 1:positive */

          /* determine sign of orginal value: */
          switch (src_type)
        {
        case DB_TYPE_INTEGER:
          is_positive = ((db_get_int (&value->dbvalue) >= 0) ? 1 : 0);
          break;
        case DB_TYPE_SMALLINT:
          is_positive = ((db_get_short (&value->dbvalue) >= 0) ? 1 : 0);
          break;
        case DB_TYPE_BIGINT:
          is_positive = ((db_get_bigint (&value->dbvalue) >= 0) ? 1 : 0);
          break;
        case DB_TYPE_FLOAT:
          is_positive = ((db_get_float (&value->dbvalue) >= 0) ? 1 : 0);
          break;
        case DB_TYPE_DOUBLE:
          is_positive = ((db_get_double (&value->dbvalue) >= 0) ? 1 : 0);
          break;
        case DB_TYPE_NUMERIC:
          is_positive = numeric_db_value_is_positive (&value->dbvalue);
          break;
        case DB_TYPE_MONETARY:
          is_positive = ((db_get_monetary (&value->dbvalue)->amount >= 0) ? 1 : 0);
          break;

        case DB_TYPE_CHAR:
        case DB_TYPE_VARCHAR:
        case DB_TYPE_NCHAR:
        case DB_TYPE_VARNCHAR:
          {
            char *str = db_get_string (&(value->dbvalue));
            char *str_end = str + db_get_string_length (&(value->dbvalue));
            char *p = NULL;

            /* get the sign in the source string; look directly into the buffer string, no copy */
            p = str;
            while (char_isspace (*p) && p < str_end)
              {
            p++;
              }

            is_positive = ((p < str_end && (*p) == '-') ? 0 : 1);
            break;
          }

        default:
          is_positive = -1;
          break;
        }

          if (is_positive == 1)
        {
          set_max_value = true;
        }
          else if (is_positive == 0)
        {
          set_min_value = true;
        }
          else
        {
          set_default_value = true;
        }
        }
      else
        {
          set_default_value = true;
        }
      /* clear the error */
      er_clear ();

      log_warning = true;

      /* the casted value will be overwritten, so a clear is needed, here */
      pr_clear_value (&(value->dbvalue));

      if (set_max_value)
        {
          /* set max value of destination domain */
          error =
        db_value_domain_max (&(value->dbvalue), dest_type, dest_prec, dest_dom->scale, dest_dom->codeset,
                     dest_dom->collation_id, &dest_dom->enumeration);
          if (error != NO_ERROR)
        {
          /* this should not happen */
          goto exit;
        }

          warning_code = ER_ALTER_CHANGE_CAST_FAILED_SET_MAX;
        }
      else if (set_min_value)
        {
          /* set min value of destination domain */
          error =
        db_value_domain_min (&(value->dbvalue), dest_type, dest_prec, dest_dom->scale, dest_dom->codeset,
                     dest_dom->collation_id, &dest_dom->enumeration);
          if (error != NO_ERROR)
        {
          /* this should not happen */
          goto exit;
        }
          warning_code = ER_ALTER_CHANGE_CAST_FAILED_SET_MIN;
        }
      else
        {
          assert (set_default_value == true);

          /* set default value of destination domain */
          error =
        db_value_domain_default (&(value->dbvalue), dest_type, dest_prec, dest_dom->scale, dest_dom->codeset,
                     dest_dom->collation_id, &dest_dom->enumeration);
          if (error != NO_ERROR)
        {
          /* this should not happen */
          goto exit;
        }
          warning_code = ER_ALTER_CHANGE_CAST_FAILED_SET_DEFAULT;
        }
    }

      if (!DB_IS_NULL (&orig_value))
    {
      assert (!DB_IS_NULL (&(value->dbvalue)));
    }

      if (log_warning)
    {
      assert (warning_code != NO_ERROR);

      /* Since we don't like to bother callers with the following warning which is just for a logging, it will be
       * poped once it is set. */
      er_stack_push ();

      if (warning_code == ER_QPROC_SIZE_STRING_TRUNCATED)
        {
          er_set (ER_WARNING_SEVERITY, ARG_FILE_LINE, warning_code, 1, "ALTER TABLE .. CHANGE");
        }
      else
        {
          er_set (ER_WARNING_SEVERITY, ARG_FILE_LINE, warning_code, 0);
        }

      /* forget the warning */
      er_stack_pop ();
    }

      value->state = HEAP_WRITTEN_ATTRVALUE;
      atts_id[updated_n_attrs_id] = value->attrid;
      updated_n_attrs_id++;

      break;
    }

  /* exactly one attribute should be changed */
  assert (updated_n_attrs_id == 1);

  if (updated_n_attrs_id != 1 || attr_info->read_classrepr == NULL || attr_info->last_classrepr == NULL
      || attr_info->read_classrepr->id >= attr_info->last_classrepr->id)
    {
      error = ER_UNEXPECTED;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, error, 1, "Incorrect attribute information.");
      goto exit;
    }

  /* the class has XCH_M_LOCK */
  error =
    locator_attribute_info_force (thread_p, &upd_scancache->node.hfid, oid, attr_info, atts_id, updated_n_attrs_id,
                  LC_FLUSH_UPDATE, SINGLE_ROW_UPDATE, upd_scancache, &force_count, false,
                  REPL_INFO_TYPE_RBR_NORMAL, DB_NOT_PARTITIONED_CLASS, NULL, NULL, NULL,
                  UPDATE_INPLACE_OLD_MVCCID, NULL, false);
  if (error != NO_ERROR)
    {
      if (error == ER_MVCC_NOT_SATISFIED_REEVALUATION)
    {
      error = NO_ERROR;
    }

      goto exit;
    }

exit:
  pr_clear_value (&orig_value);
  return error;
}

/*
 * heap_eval_function_index - evaluate the result of the expression used in
 *                a function index.
 *
 *    thread_p(in) : thread context
 *    func_index_info(in): function index information
 *    n_atts(in): number of attributes involved
 *    att_ids(in): attribute identifiers
 *    attr_info(in): attribute info structure
 *    recdes(in): record descriptor
 *    btid_index(in): id of the function index used
 *    func_pred_cache(in): cached function index expressions
 *    result(out): result of the function expression
 *    fi_domain(out): domain of function index (from regu_var)
 *    return: error code
 */
static int
heap_eval_function_index (THREAD_ENTRY * thread_p, FUNCTION_INDEX_INFO * func_index_info, int n_atts, int *att_ids,
              HEAP_CACHE_ATTRINFO * attr_info, RECDES * recdes, int btid_index, DB_VALUE * result,
              FUNC_PRED_UNPACK_INFO * func_pred_cache, TP_DOMAIN ** fi_domain)
{
  int error = NO_ERROR;
  OR_INDEX *index = NULL;
  char *expr_stream = NULL;
  int expr_stream_size = 0;
  FUNC_PRED *func_pred = NULL;
  void *unpack_info = NULL;
  DB_VALUE *res = NULL;
  int i, nr_atts;
  ATTR_ID *atts = NULL;
  bool atts_free = false, attrinfo_clear = false, attrinfo_end = false;
  HEAP_CACHE_ATTRINFO *cache_attr_info = NULL;

  if (func_index_info == NULL && btid_index > -1 && n_atts == -1)
    {
      index = &(attr_info->last_classrepr->indexes[btid_index]);
      if (func_pred_cache)
    {
      func_pred = (FUNC_PRED *) func_pred_cache->func_pred;
      cache_attr_info = func_pred->cache_attrinfo;
      nr_atts = index->n_atts;
    }
      else
    {
      expr_stream = index->func_index_info->expr_stream;
      expr_stream_size = index->func_index_info->expr_stream_size;
      nr_atts = index->n_atts;
      atts = (ATTR_ID *) malloc (nr_atts * sizeof (ATTR_ID));
      if (atts == NULL)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, nr_atts * sizeof (ATTR_ID));
          error = ER_FAILED;
          goto end;
        }
      atts_free = true;
      for (i = 0; i < nr_atts; i++)
        {
          atts[i] = index->atts[i]->id;
        }
      cache_attr_info = attr_info;
    }
    }
  else
    {
      /* load index case */
      expr_stream = func_index_info->expr_stream;
      expr_stream_size = func_index_info->expr_stream_size;
      nr_atts = n_atts;
      atts = att_ids;
      cache_attr_info = ((FUNC_PRED *) func_index_info->expr)->cache_attrinfo;
      func_pred = (FUNC_PRED *) func_index_info->expr;
    }

  if (func_index_info == NULL)
    {
      /* insert case, read the values */
      if (func_pred == NULL)
    {
      if (stx_map_stream_to_func_pred (thread_p, (FUNC_PRED **) (&func_pred), expr_stream, expr_stream_size,
                       &unpack_info))
        {
          error = ER_FAILED;
          goto end;
        }
      cache_attr_info = func_pred->cache_attrinfo;

      if (heap_attrinfo_start (thread_p, &attr_info->class_oid, nr_atts, atts, cache_attr_info) != NO_ERROR)
        {
          error = ER_FAILED;
          goto end;
        }
      attrinfo_end = true;
    }

      if (heap_attrinfo_read_dbvalues (thread_p, &attr_info->inst_oid, recdes, NULL, cache_attr_info) != NO_ERROR)
    {
      error = ER_FAILED;
      goto end;
    }
      attrinfo_clear = true;
    }

  error =
    fetch_peek_dbval (thread_p, func_pred->func_regu, NULL, &cache_attr_info->class_oid, &cache_attr_info->inst_oid,
              NULL, &res);
  if (error == NO_ERROR)
    {
      pr_clone_value (res, result);
    }

  if (fi_domain != NULL)
    {
      *fi_domain = tp_domain_cache (func_pred->func_regu->domain);
    }

  if (res != NULL && res->need_clear == true)
    {
      pr_clear_value (res);
    }

end:
  if (attrinfo_clear && cache_attr_info)
    {
      heap_attrinfo_clear_dbvalues (cache_attr_info);
    }
  if (attrinfo_end && cache_attr_info)
    {
      heap_attrinfo_end (thread_p, cache_attr_info);
    }
  if (atts_free && atts)
    {
      free_and_init (atts);
    }
  if (unpack_info)
    {
      (void) qexec_clear_func_pred (thread_p, func_pred);
      stx_free_additional_buff (thread_p, unpack_info);
      stx_free_xasl_unpack_info (unpack_info);
      db_private_free_and_init (thread_p, unpack_info);
    }

  return error;
}

/*
 * heap_init_func_pred_unpack_info () - if function indexes are found,
 *          each function expression is unpacked and cached
 *          in order to be used during bulk inserts
 *          (insert ... select).
 *   return: NO_ERROR, or ER_FAILED
 *   thread_p(in): thread entry
 *   attr_info(in): heap_cache_attrinfo
 *   class_oid(in): the class oid
 *   func_indx_preds(out):
 */
int
heap_init_func_pred_unpack_info (THREAD_ENTRY * thread_p, HEAP_CACHE_ATTRINFO * attr_info, const OID * class_oid,
                 FUNC_PRED_UNPACK_INFO ** func_indx_preds)
{
  OR_FUNCTION_INDEX *fi_info = NULL;
  int n_indexes;
  int i, j;
  int *att_ids = NULL;
  int error_status = NO_ERROR;
  OR_INDEX *idx;
  FUNC_PRED_UNPACK_INFO *fi_preds = NULL;
  int *attr_info_started = NULL;
  size_t size;

  if (attr_info == NULL || class_oid == NULL || func_indx_preds == NULL)
    {
      return ER_FAILED;
    }

  *func_indx_preds = NULL;

  n_indexes = attr_info->last_classrepr->n_indexes;
  for (i = 0; i < n_indexes; i++)
    {
      idx = &(attr_info->last_classrepr->indexes[i]);
      fi_info = idx->func_index_info;
      if (fi_info)
    {
      if (fi_preds == NULL)
        {
          size = n_indexes * sizeof (FUNC_PRED_UNPACK_INFO);
          fi_preds = (FUNC_PRED_UNPACK_INFO *) db_private_alloc (thread_p, size);
          if (!fi_preds)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, size);
          error_status = ER_FAILED;
          goto error;
        }
          for (j = 0; j < n_indexes; j++)
        {
          fi_preds[j].func_pred = NULL;
          fi_preds[j].unpack_info = NULL;
        }

          size = n_indexes * sizeof (int);
          attr_info_started = (int *) db_private_alloc (thread_p, size);
          if (attr_info_started == NULL)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, size);
          error_status = ER_FAILED;
          goto error;
        }
          for (j = 0; j < n_indexes; j++)
        {
          attr_info_started[j] = 0;
        }
        }

      if (stx_map_stream_to_func_pred (thread_p, (FUNC_PRED **) (&(fi_preds[i].func_pred)),
                       fi_info->expr_stream, fi_info->expr_stream_size, &(fi_preds[i].unpack_info)))
        {
          error_status = ER_FAILED;
          goto error;
        }

      size = idx->n_atts * sizeof (ATTR_ID);
      att_ids = (ATTR_ID *) db_private_alloc (thread_p, size);
      if (!att_ids)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, size);
          error_status = ER_FAILED;
          goto error;
        }

      for (j = 0; j < idx->n_atts; j++)
        {
          att_ids[j] = idx->atts[j]->id;
        }

      if (heap_attrinfo_start (thread_p, class_oid, idx->n_atts, att_ids,
                   ((FUNC_PRED *) fi_preds[i].func_pred)->cache_attrinfo) != NO_ERROR)
        {
          error_status = ER_FAILED;
          goto error;
        }

      attr_info_started[i] = 1;

      if (att_ids)
        {
          db_private_free_and_init (thread_p, att_ids);
        }
    }
    }

  if (attr_info_started != NULL)
    {
      db_private_free_and_init (thread_p, attr_info_started);
    }

  *func_indx_preds = fi_preds;

  return NO_ERROR;

error:
  if (att_ids)
    {
      db_private_free_and_init (thread_p, att_ids);
    }
  heap_free_func_pred_unpack_info (thread_p, n_indexes, fi_preds, attr_info_started);
  if (attr_info_started != NULL)
    {
      db_private_free_and_init (thread_p, attr_info_started);
    }

  return error_status;
}

/*
 * heap_free_func_pred_unpack_info () -
 *   return:
 *   thread_p(in): thread entry
 *   n_indexes(in): number of indexes
 *   func_indx_preds(in):
 *   attr_info_started(in): array of int (1 if corresponding cache_attrinfo
 *                    must be cleaned, 0 otherwise)
 *              if null all cache_attrinfo must be cleaned
 */
void
heap_free_func_pred_unpack_info (THREAD_ENTRY * thread_p, int n_indexes, FUNC_PRED_UNPACK_INFO * func_indx_preds,
                 int *attr_info_started)
{
  int i;

  if (func_indx_preds == NULL)
    {
      return;
    }

  for (i = 0; i < n_indexes; i++)
    {
      if (func_indx_preds[i].func_pred)
    {
      if (attr_info_started == NULL || attr_info_started[i])
        {
          assert (((FUNC_PRED *) func_indx_preds[i].func_pred)->cache_attrinfo);
          (void) heap_attrinfo_end (thread_p, ((FUNC_PRED *) func_indx_preds[i].func_pred)->cache_attrinfo);
        }
      (void) qexec_clear_func_pred (thread_p, (FUNC_PRED *) func_indx_preds[i].func_pred);
    }

      if (func_indx_preds[i].unpack_info)
    {
      stx_free_additional_buff (thread_p, func_indx_preds[i].unpack_info);
      stx_free_xasl_unpack_info (func_indx_preds[i].unpack_info);
      db_private_free_and_init (thread_p, func_indx_preds[i].unpack_info);
    }
    }
  db_private_free_and_init (thread_p, func_indx_preds);
}

/*
 * heap_header_capacity_start_scan () - start scan function for 'show heap ...'
 *   return: NO_ERROR, or ER_code
 *   thread_p(in): thread entry
 *   show_type(in):
 *   arg_values(in):
 *   arg_cnt(in):
 *   ptr(in/out): 'show heap' context
 */
int
heap_header_capacity_start_scan (THREAD_ENTRY * thread_p, int show_type, DB_VALUE ** arg_values, int arg_cnt,
                 void **ptr)
{
  int error = NO_ERROR;
  char *class_name = NULL;
  DB_CLASS_PARTITION_TYPE partition_type = DB_NOT_PARTITIONED_CLASS;
  OID class_oid;
  LC_FIND_CLASSNAME status;
  HEAP_SHOW_SCAN_CTX *ctx = NULL;
  OR_PARTITION *parts = NULL;
  int i = 0;
  int parts_count = 0;
  bool is_all = false;

  assert (arg_cnt == 2);
  assert (DB_VALUE_TYPE (arg_values[0]) == DB_TYPE_CHAR);
  assert (DB_VALUE_TYPE (arg_values[1]) == DB_TYPE_INTEGER);

  *ptr = NULL;

  class_name = db_get_string (arg_values[0]);

  partition_type = (DB_CLASS_PARTITION_TYPE) db_get_int (arg_values[1]);

  ctx = (HEAP_SHOW_SCAN_CTX *) db_private_alloc (thread_p, sizeof (HEAP_SHOW_SCAN_CTX));
  if (ctx == NULL)
    {
      ASSERT_ERROR ();
      error = er_errid ();
      goto cleanup;
    }
  memset (ctx, 0, sizeof (HEAP_SHOW_SCAN_CTX));

  status = xlocator_find_class_oid (thread_p, class_name, &class_oid, S_LOCK);
  if (status == LC_CLASSNAME_ERROR || status == LC_CLASSNAME_DELETED)
    {
      error = ER_LC_UNKNOWN_CLASSNAME;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, error, 1, class_name);
      goto cleanup;
    }

  is_all = (show_type == SHOWSTMT_ALL_HEAP_HEADER || show_type == SHOWSTMT_ALL_HEAP_CAPACITY);

  if (is_all && partition_type == DB_PARTITIONED_CLASS)
    {
      error = heap_get_class_partitions (thread_p, &class_oid, &parts, &parts_count);
      if (error != NO_ERROR)
    {
      goto cleanup;
    }

      ctx->hfids = (HFID *) db_private_alloc (thread_p, parts_count * sizeof (HFID));
      if (ctx->hfids == NULL)
    {
      ASSERT_ERROR ();
      error = er_errid ();
      goto cleanup;
    }

      for (i = 0; i < parts_count; i++)
    {
      HFID_COPY (&ctx->hfids[i], &parts[i].class_hfid);
    }

      ctx->hfids_count = parts_count;
    }
  else
    {
      ctx->hfids = (HFID *) db_private_alloc (thread_p, sizeof (HFID));
      if (ctx->hfids == NULL)
    {
      ASSERT_ERROR ();
      error = er_errid ();
      goto cleanup;
    }

      error = heap_get_hfid_from_class_oid (thread_p, &class_oid, &ctx->hfids[0]);
      if (error != NO_ERROR)
    {
      goto cleanup;
    }

      ctx->hfids_count = 1;
    }

  *ptr = ctx;
  ctx = NULL;

cleanup:

  if (parts != NULL)
    {
      heap_clear_partition_info (thread_p, parts, parts_count);
    }

  if (ctx != NULL)
    {
      if (ctx->hfids != NULL)
    {
      db_private_free (thread_p, ctx->hfids);
    }

      db_private_free_and_init (thread_p, ctx);
    }

  return error;
}

/*
 * heap_header_next_scan () - next scan function for
 *                            'show (all) heap header'
 *   return: NO_ERROR, or ER_code
 *   thread_p(in):
 *   cursor(in):
 *   out_values(in/out):
 *   out_cnt(in):
 *   ptr(in): 'show heap' context
 */
SCAN_CODE
heap_header_next_scan (THREAD_ENTRY * thread_p, int cursor, DB_VALUE ** out_values, int out_cnt, void *ptr)
{
  int error = NO_ERROR;
  HEAP_SHOW_SCAN_CTX *ctx = NULL;
  VPID vpid;
  HEAP_HDR_STATS *heap_hdr = NULL;
  RECDES hdr_recdes;
  int i = 0;
  int idx = 0;
  PAGE_PTR pgptr = NULL;
  HFID *hfid_p;
  char *class_name = NULL;
  int avg_length = 0;
  char buf[512] = { 0 };
  char temp[64] = { 0 };
  char *buf_p, *end;

  ctx = (HEAP_SHOW_SCAN_CTX *) ptr;

  if (cursor >= ctx->hfids_count)
    {
      return S_END;
    }

  hfid_p = &ctx->hfids[cursor];

  vpid.volid = hfid_p->vfid.volid;
  vpid.pageid = hfid_p->hpgid;

  pgptr = heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, S_LOCK, NULL, NULL);
  if (pgptr == NULL)
    {
      ASSERT_ERROR ();
      error = er_errid ();
      goto cleanup;
    }

  if (spage_get_record (thread_p, pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &hdr_recdes, PEEK) != S_SUCCESS)
    {
      error = ER_SP_INVALID_HEADER;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, error, 3, vpid.pageid, fileio_get_volume_label (vpid.volid, PEEK), 0);
      goto cleanup;
    }

  heap_hdr = (HEAP_HDR_STATS *) hdr_recdes.data;

  if (heap_get_class_name (thread_p, &(heap_hdr->class_oid), &class_name) != NO_ERROR || class_name == NULL)
    {
      ASSERT_ERROR_AND_SET (error);
      goto cleanup;
    }

  idx = 0;

  /* Class_name */
  error = db_make_string_copy (out_values[idx], class_name);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  /* Class_oid */
  oid_to_string (buf, sizeof (buf), &heap_hdr->class_oid);
  error = db_make_string_copy (out_values[idx], buf);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  /* HFID */
  db_make_int (out_values[idx], hfid_p->vfid.volid);
  idx++;

  db_make_int (out_values[idx], hfid_p->vfid.fileid);
  idx++;

  db_make_int (out_values[idx], hfid_p->hpgid);
  idx++;

  /* Overflow_vfid */
  vfid_to_string (buf, sizeof (buf), &heap_hdr->ovf_vfid);
  error = db_make_string_copy (out_values[idx], buf);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  /* Next_vpid */
  vpid_to_string (buf, sizeof (buf), &heap_hdr->next_vpid);
  error = db_make_string_copy (out_values[idx], buf);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  /* Unfill space */
  db_make_int (out_values[idx], heap_hdr->unfill_space);
  idx++;

  /* Estimated */
  db_make_bigint (out_values[idx], heap_hdr->estimates.num_pages);
  idx++;

  db_make_bigint (out_values[idx], heap_hdr->estimates.num_recs);
  idx++;

  avg_length = ((heap_hdr->estimates.num_recs > 0)
        ? (int) ((heap_hdr->estimates.recs_sumlen / (float) heap_hdr->estimates.num_recs) + 0.9) : 0);
  db_make_int (out_values[idx], avg_length);
  idx++;

  db_make_int (out_values[idx], heap_hdr->estimates.num_high_best);
  idx++;

  db_make_int (out_values[idx], heap_hdr->estimates.num_other_high_best);
  idx++;

  db_make_int (out_values[idx], heap_hdr->estimates.head);
  idx++;

  /* Estimates_best_list */
  buf_p = buf;
  end = buf + sizeof (buf);
  for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      if (i > 0)
    {
      if (fill_string_to_buffer (&buf_p, end, ", ") == -1)
        {
          break;
        }
    }

      heap_bestspace_to_string (temp, sizeof (temp), heap_hdr->estimates.best + i);
      if (fill_string_to_buffer (&buf_p, end, temp) == -1)
    {
      break;
    }
    }

  error = db_make_string_copy (out_values[idx], buf);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  db_make_int (out_values[idx], heap_hdr->estimates.num_second_best);
  idx++;

  db_make_int (out_values[idx], heap_hdr->estimates.head_second_best);
  idx++;

  db_make_int (out_values[idx], heap_hdr->estimates.tail_second_best);
  idx++;

  db_make_int (out_values[idx], heap_hdr->estimates.num_substitutions);
  idx++;

  /* Estimates_second_best */
  buf_p = buf;
  end = buf + sizeof (buf);
  for (i = 0; i < HEAP_NUM_BEST_SPACESTATS; i++)
    {
      if (i > 0)
    {
      if (fill_string_to_buffer (&buf_p, end, ", ") == -1)
        {
          break;
        }
    }

      vpid_to_string (temp, sizeof (temp), heap_hdr->estimates.second_best + i);
      if (fill_string_to_buffer (&buf_p, end, temp) == -1)
    {
      break;
    }
    }

  error = db_make_string_copy (out_values[idx], buf);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  vpid_to_string (buf, sizeof (buf), &heap_hdr->estimates.last_vpid);
  error = db_make_string_copy (out_values[idx], buf);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  vpid_to_string (buf, sizeof (buf), &heap_hdr->estimates.full_search_vpid);
  error = db_make_string_copy (out_values[idx], buf);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  assert (idx == out_cnt);

cleanup:

  if (pgptr != NULL)
    {
      pgbuf_unfix_and_init (thread_p, pgptr);
    }

  if (class_name != NULL)
    {
      free_and_init (class_name);
    }

  return (error == NO_ERROR) ? S_SUCCESS : S_ERROR;
}

/*
 * heap_capacity_next_scan () - next scan function for
 *                              'show (all) heap capacity'
 *   return: NO_ERROR, or ER_code
 *   thread_p(in):
 *   cursor(in):
 *   out_values(in/out):
 *   out_cnt(in):
 *   ptr(in): 'show heap' context
 */
SCAN_CODE
heap_capacity_next_scan (THREAD_ENTRY * thread_p, int cursor, DB_VALUE ** out_values, int out_cnt, void *ptr)
{
  int error = NO_ERROR;
  HEAP_SHOW_SCAN_CTX *ctx = NULL;
  HFID *hfid_p = NULL;
  HEAP_CACHE_ATTRINFO attr_info;
  OR_CLASSREP *repr = NULL;
  char *classname = NULL;
  char class_oid_str[64] = { 0 };
  bool is_heap_attrinfo_started = false;
  INT64 num_recs = 0;
  INT64 num_relocated_recs = 0;
  INT64 num_overflowed_recs = 0;
  INT64 num_pages = 0;
  int avg_rec_len = 0;
  int avg_free_space_per_page = 0;
  int avg_free_space_without_last_page = 0;
  int avg_overhead_per_page = 0;
  int val = 0;
  int idx = 0;
  FILE_DESCRIPTORS fdes;

  ctx = (HEAP_SHOW_SCAN_CTX *) ptr;

  if (cursor >= ctx->hfids_count)
    {
      return S_END;
    }

  hfid_p = &ctx->hfids[cursor];

  error =
    heap_get_capacity (thread_p, hfid_p, &num_recs, &num_relocated_recs, &num_overflowed_recs, &num_pages,
               &avg_free_space_per_page, &avg_free_space_without_last_page, &avg_rec_len,
               &avg_overhead_per_page);
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  error = file_descriptor_get (thread_p, &hfid_p->vfid, &fdes);
  if (error != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto cleanup;
    }

  error = heap_attrinfo_start (thread_p, &fdes.heap.class_oid, -1, NULL, &attr_info);
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  is_heap_attrinfo_started = true;

  repr = attr_info.last_classrepr;
  if (repr == NULL)
    {
      error = ER_HEAP_UNKNOWN_OBJECT;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, error, 3, fdes.heap.class_oid.volid, fdes.heap.class_oid.pageid,
          fdes.heap.class_oid.slotid);
      goto cleanup;
    }

  if (heap_get_class_name (thread_p, &fdes.heap.class_oid, &classname) != NO_ERROR || classname == NULL)
    {
      ASSERT_ERROR_AND_SET (error);
      goto cleanup;
    }

  idx = 0;

  error = db_make_string_copy (out_values[idx], classname);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  oid_to_string (class_oid_str, sizeof (class_oid_str), &fdes.heap.class_oid);
  error = db_make_string_copy (out_values[idx], class_oid_str);
  idx++;
  if (error != NO_ERROR)
    {
      goto cleanup;
    }

  db_make_int (out_values[idx], hfid_p->vfid.volid);
  idx++;

  db_make_int (out_values[idx], hfid_p->vfid.fileid);
  idx++;

  db_make_int (out_values[idx], hfid_p->hpgid);
  idx++;

  db_make_bigint (out_values[idx], num_recs);
  idx++;

  db_make_bigint (out_values[idx], num_relocated_recs);
  idx++;

  db_make_bigint (out_values[idx], num_overflowed_recs);
  idx++;

  db_make_bigint (out_values[idx], num_pages);
  idx++;

  db_make_int (out_values[idx], avg_rec_len);
  idx++;

  db_make_int (out_values[idx], avg_free_space_per_page);
  idx++;

  db_make_int (out_values[idx], avg_free_space_without_last_page);
  idx++;

  db_make_int (out_values[idx], avg_overhead_per_page);
  idx++;

  db_make_int (out_values[idx], repr->id);
  idx++;

  db_make_int (out_values[idx], repr->n_attributes);
  idx++;

  val = repr->n_attributes - repr->n_variable - repr->n_shared_attrs - repr->n_class_attrs;
  db_make_int (out_values[idx], val);
  idx++;

  db_make_int (out_values[idx], repr->n_variable);
  idx++;

  db_make_int (out_values[idx], repr->n_shared_attrs);
  idx++;

  db_make_int (out_values[idx], repr->n_class_attrs);
  idx++;

  db_make_int (out_values[idx], repr->fixed_length);
  idx++;

  assert (idx == out_cnt);

cleanup:

  if (classname != NULL)
    {
      free_and_init (classname);
    }

  if (is_heap_attrinfo_started)
    {
      heap_attrinfo_end (thread_p, &attr_info);
    }

  return (error == NO_ERROR) ? S_SUCCESS : S_ERROR;
}

/*
 *  heap_header_capacity_end_scan() - end scan function of
 *                                    'show (all) heap ...'
 *   return: NO_ERROR, or ER_code
 *   thread_p(in):
 *   ptr(in/out): 'show heap' context
 */
int
heap_header_capacity_end_scan (THREAD_ENTRY * thread_p, void **ptr)
{
  HEAP_SHOW_SCAN_CTX *ctx;

  ctx = (HEAP_SHOW_SCAN_CTX *) (*ptr);

  if (ctx == NULL)
    {
      return NO_ERROR;
    }

  if (ctx->hfids != NULL)
    {
      db_private_free (thread_p, ctx->hfids);
    }

  db_private_free (thread_p, ctx);
  *ptr = NULL;

  return NO_ERROR;
}

static char *
heap_bestspace_to_string (char *buf, int buf_size, const HEAP_BESTSPACE * hb)
{
  snprintf (buf, buf_size, "((%d|%d), %d)", hb->vpid.volid, hb->vpid.pageid, hb->freespace);
  buf[buf_size - 1] = '\0';

  return buf;
}

/*
 * fill_string_to_buffer () - fill string into buffer
 *
 *   -----------------------------
 *   |        buffer             |
 *   -----------------------------
 *   ^                           ^
 *   |                           |
 *   start                       end
 *
 *   return: the count of characters (not include '\0') which has been
 *           filled into buffer; -1 means error.
 *   start(in/out): After filling, start move to the '\0' position.
 *   end(in): The first unavailble position.
 *   str(in):
 */
static int
fill_string_to_buffer (char **start, char *end, const char *str)
{
  int len = (int) strlen (str);

  if (*start + len >= end)
    {
      return -1;
    }

  memcpy (*start, str, len);
  *start += len;
  **start = '\0';

  return len;
}

/*
 * heap_get_page_info () - Obtain page information.
 *
 * return     : SCAN_CODE.
 * thread_p (in)  : Thread entry.
 * cls_oid (in)   : Class object identifier.
 * hfid (in)      : Heap file identifier.
 * vpid (in)      : Page identifier.
 * pgptr (in)     : Pointer to the cached page.
 * page_info (in) : Pointers to DB_VALUES where page information is stored.
 */
static SCAN_CODE
heap_get_page_info (THREAD_ENTRY * thread_p, const OID * cls_oid, const HFID * hfid, const VPID * vpid,
            const PAGE_PTR pgptr, DB_VALUE ** page_info)
{
  RECDES recdes;

  if (page_info == NULL)
    {
      /* no need to get page info */
      return S_SUCCESS;
    }

  if (spage_get_record (thread_p, pgptr, HEAP_HEADER_AND_CHAIN_SLOTID, &recdes, PEEK) != S_SUCCESS)
    {
      /* Error obtaining header slot */
      return S_ERROR;
    }

  db_make_oid (page_info[HEAP_PAGE_INFO_CLASS_OID], cls_oid);

  if (hfid->hpgid == vpid->pageid && hfid->vfid.volid == vpid->volid)
    {
      HEAP_HDR_STATS *hdr_stats = (HEAP_HDR_STATS *) recdes.data;
      db_make_null (page_info[HEAP_PAGE_INFO_PREV_PAGE]);
      db_make_int (page_info[HEAP_PAGE_INFO_NEXT_PAGE], hdr_stats->next_vpid.pageid);
    }
  else
    {
      HEAP_CHAIN *chain = (HEAP_CHAIN *) recdes.data;
      db_make_int (page_info[HEAP_PAGE_INFO_PREV_PAGE], chain->prev_vpid.pageid);
      db_make_int (page_info[HEAP_PAGE_INFO_NEXT_PAGE], chain->next_vpid.pageid);
    }

  /* Obtain information from spage header */
  return spage_get_page_header_info (pgptr, page_info);
}

/*
 * heap_page_next () - Advance to next page in chain and obtain information.
 *
 * return          : SCAN_CODE.
 * thread_p (in)       : Thread entry.
 * class_oid (in)      : Class object identifier.
 * hfid (in)           : Heap file identifier.
 * next_vpid (in)      : Next page identifier.
 * cache_pageinfo (in) : Pointers to DB_VALUEs where page information is
 *           stored.
 */
SCAN_CODE
heap_page_next (THREAD_ENTRY * thread_p, const OID * class_oid, const HFID * hfid, VPID * next_vpid,
        DB_VALUE ** cache_pageinfo)
{
  PGBUF_WATCHER pg_watcher;
  PGBUF_WATCHER old_pg_watcher;
  SCAN_CODE scan = S_SUCCESS;

  PGBUF_INIT_WATCHER (&pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&old_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  /* get next page */
  if (VPID_ISNULL (next_vpid))
    {
      /* set to first page */
      next_vpid->pageid = hfid->hpgid;
      next_vpid->volid = hfid->vfid.volid;
    }
  else
    {
      pg_watcher.pgptr = heap_scan_pb_lock_and_fetch (thread_p, next_vpid, OLD_PAGE, S_LOCK, NULL, &pg_watcher);
      if (pg_watcher.pgptr == NULL)
    {
      return S_ERROR;
    }
      /* get next page */
      heap_vpid_next (thread_p, hfid, pg_watcher.pgptr, next_vpid);
      if (OID_ISNULL (next_vpid))
    {
      /* no more pages to scan */
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
      return S_END;
    }
      pgbuf_replace_watcher (thread_p, &pg_watcher, &old_pg_watcher);
    }

  /* get page pointer to next page */
  pg_watcher.pgptr =
    heap_scan_pb_lock_and_fetch (thread_p, next_vpid, OLD_PAGE_PREVENT_DEALLOC, S_LOCK, NULL, &pg_watcher);
  if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }
  if (pg_watcher.pgptr == NULL)
    {
      return S_ERROR;
    }

  /* read page information and return scan code */
  scan = heap_get_page_info (thread_p, class_oid, hfid, next_vpid, pg_watcher.pgptr, cache_pageinfo);

  pgbuf_ordered_unfix (thread_p, &pg_watcher);
  return scan;
}

/*
 * heap_page_prev () - Advance to previous page in chain and obtain
 *             information.
 *
 * return          : SCAN_CODE.
 * thread_p (in)       : Thread entry.
 * class_oid (in)      : Class object identifier.
 * hfid (in)           : Heap file identifier.
 * prev_vpid (in)      : Previous page identifier.
 * cache_pageinfo (in) : Pointers to DB_VALUEs where page information is
 *           stored.
 */
SCAN_CODE
heap_page_prev (THREAD_ENTRY * thread_p, const OID * class_oid, const HFID * hfid, VPID * prev_vpid,
        DB_VALUE ** cache_pageinfo)
{
  PGBUF_WATCHER pg_watcher;
  PGBUF_WATCHER old_pg_watcher;
  SCAN_CODE scan = S_SUCCESS;

  PGBUF_INIT_WATCHER (&pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);
  PGBUF_INIT_WATCHER (&old_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid);

  /* get next page */
  if (VPID_ISNULL (prev_vpid))
    {
      /* set to last page */
      if (heap_get_last_vpid (thread_p, hfid, prev_vpid) != NO_ERROR)
    {
      ASSERT_ERROR ();
      return S_ERROR;
    }
    }
  else
    {
      pg_watcher.pgptr = heap_scan_pb_lock_and_fetch (thread_p, prev_vpid, OLD_PAGE, S_LOCK, NULL, &pg_watcher);
      if (pg_watcher.pgptr == NULL)
    {
      return S_ERROR;
    }
      /* get next page */
      heap_vpid_prev (thread_p, hfid, pg_watcher.pgptr, prev_vpid);
      if (OID_ISNULL (prev_vpid))
    {
      /* no more pages to scan */
      return S_END;
    }
      /* get next page */
      pgbuf_replace_watcher (thread_p, &pg_watcher, &old_pg_watcher);
    }

  pg_watcher.pgptr =
    heap_scan_pb_lock_and_fetch (thread_p, prev_vpid, OLD_PAGE_PREVENT_DEALLOC, S_LOCK, NULL, &pg_watcher);
  if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }
  if (pg_watcher.pgptr == NULL)
    {
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
      return S_ERROR;
    }

  /* read page information and return scan code */
  scan = heap_get_page_info (thread_p, class_oid, hfid, prev_vpid, pg_watcher.pgptr, cache_pageinfo);

  pgbuf_ordered_unfix (thread_p, &pg_watcher);
  return scan;
}

/*
 * heap_get_record_info () - Heap function to obtain record information and
 *               record data.
 *
 * return          : SCAN CODE (S_SUCCESS or S_ERROR).
 * thread_p (in)       : Thread entry.
 * oid (in)        : Object identifier.
 * recdes (out)        : Record descriptor (to save record data).
 * forward_recdes (in) : Record descriptor used by REC_RELOCATION & REC_BIGONE
 *           records.
 * pgptr (in/out)      : Pointer to the page this object belongs to.
 * scan_cache (in)     : Heap scan cache.
 * ispeeking (in)      : PEEK/COPY.
 * record_info (out)   : Stores record information.
 */
static SCAN_CODE
heap_get_record_info (THREAD_ENTRY * thread_p, const OID oid, RECDES * recdes, RECDES forward_recdes,
              PGBUF_WATCHER * page_watcher, HEAP_SCANCACHE * scan_cache, bool ispeeking,
              DB_VALUE ** record_info)
{
  SPAGE_SLOT *slot_p = NULL;
  SCAN_CODE scan = S_SUCCESS;
  OID forward_oid;
  MVCC_REC_HEADER mvcc_header;

  assert (page_watcher != NULL);
  assert (record_info != NULL);
  assert (recdes != NULL);

  /* careful adding values in the right order */
  db_make_int (record_info[HEAP_RECORD_INFO_T_VOLUMEID], oid.volid);
  db_make_int (record_info[HEAP_RECORD_INFO_T_PAGEID], oid.pageid);
  db_make_int (record_info[HEAP_RECORD_INFO_T_SLOTID], oid.slotid);

  /* get slot info */
  slot_p = spage_get_slot (page_watcher->pgptr, oid.slotid);
  if (slot_p == NULL)
    {
      assert (0);
    }
  db_make_int (record_info[HEAP_RECORD_INFO_T_OFFSET], slot_p->offset_to_record);
  db_make_int (record_info[HEAP_RECORD_INFO_T_LENGTH], slot_p->record_length);
  db_make_int (record_info[HEAP_RECORD_INFO_T_REC_TYPE], slot_p->record_type);

  /* get record info */
  switch (slot_p->record_type)
    {
    case REC_NEWHOME:
    case REC_HOME:
      if (scan_cache != NULL && ispeeking == COPY && recdes->data == NULL)
    {
      /* It is guaranteed that scan_cache is not NULL. */
      if (scan_cache->area == NULL)
        {
          /* Allocate an area to hold the object. Assume that the object will fit in two pages for not better
           * estimates. */
          scan_cache->area_size = DB_PAGESIZE * 2;
          scan_cache->area = (char *) db_private_alloc (thread_p, scan_cache->area_size);
          if (scan_cache->area == NULL)
        {
          scan_cache->area_size = -1;
          pgbuf_ordered_unfix (thread_p, page_watcher);
          return S_ERROR;
        }
        }
      recdes->data = scan_cache->area;
      recdes->area_size = scan_cache->area_size;
      /* The allocated space is enough to save the instance. */
    }
      if (scan_cache != NULL && scan_cache->cache_last_fix_page == true)
    {
      scan = spage_get_record (thread_p, page_watcher->pgptr, oid.slotid, recdes, ispeeking);
      pgbuf_replace_watcher (thread_p, page_watcher, &scan_cache->page_watcher);
    }
      else
    {
      scan = spage_get_record (thread_p, page_watcher->pgptr, oid.slotid, recdes, COPY);
      pgbuf_ordered_unfix (thread_p, page_watcher);
    }
      db_make_int (record_info[HEAP_RECORD_INFO_T_REPRID], or_rep_id (recdes));
      db_make_int (record_info[HEAP_RECORD_INFO_T_REPRID], or_chn (recdes));
      or_mvcc_get_header (recdes, &mvcc_header);
      db_make_bigint (record_info[HEAP_RECORD_INFO_T_MVCC_INSID], MVCC_GET_INSID (&mvcc_header));
      if (MVCC_IS_HEADER_DELID_VALID (&mvcc_header))
    {
      db_make_bigint (record_info[HEAP_RECORD_INFO_T_MVCC_DELID], MVCC_GET_DELID (&mvcc_header));
    }
      else
    {
      db_make_null (record_info[HEAP_RECORD_INFO_T_MVCC_DELID]);
    }
      db_make_int (record_info[HEAP_RECORD_INFO_T_CHN], OR_GET_MVCC_CHN (&mvcc_header));
      db_make_int (record_info[HEAP_RECORD_INFO_T_MVCC_FLAGS], MVCC_GET_FLAG (&mvcc_header));
      if (MVCC_IS_FLAG_SET (&mvcc_header, OR_MVCC_FLAG_VALID_PREV_VERSION))
    {
      db_make_int (record_info[HEAP_RECORD_INFO_T_MVCC_PREV_VERSION], 1);
    }
      else
    {
      db_make_int (record_info[HEAP_RECORD_INFO_T_MVCC_PREV_VERSION], 0);
    }
      break;

    case REC_BIGONE:
      /* Get the address of the content of the multiple page object */
      COPY_OID (&forward_oid, (OID *) forward_recdes.data);
      pgbuf_ordered_unfix (thread_p, page_watcher);

      /* Now get the content of the multiple page object. */
      /* Try to reuse the previously allocated area */
      if (scan_cache != NULL && (ispeeking == PEEK || recdes->data == NULL))
    {
      /* It is guaranteed that scan_cache is not NULL. */
      if (scan_cache->area == NULL)
        {
          /* Allocate an area to hold the object. Assume that the object will fit in two pages for not better
           * estimates. We could call heap_ovf_get_length, but it may be better to just guess and realloc if
           * needed. We could also check the estimates for average object length, but again, it may be expensive
           * and may not be accurate for the object. */
          scan_cache->area_size = DB_PAGESIZE * 2;
          scan_cache->area = (char *) db_private_alloc (thread_p, scan_cache->area_size);
          if (scan_cache->area == NULL)
        {
          scan_cache->area_size = -1;
          return S_ERROR;
        }
        }
      recdes->data = scan_cache->area;
      recdes->area_size = scan_cache->area_size;

      while ((scan = heap_ovf_get (thread_p, &forward_oid, recdes, NULL_CHN, NULL)) == S_DOESNT_FIT)
        {
          /* The object did not fit into such an area, reallocate a new area */
          recdes->area_size = -recdes->length;
          recdes->data = (char *) db_private_realloc (thread_p, scan_cache->area, recdes->area_size);
          if (recdes->data == NULL)
        {
          return S_ERROR;
        }
          scan_cache->area_size = recdes->area_size;
          scan_cache->area = recdes->data;
        }
      if (scan != S_SUCCESS)
        {
          recdes->data = NULL;
        }
    }
      else
    {
      scan = heap_ovf_get (thread_p, &forward_oid, recdes, NULL_CHN, NULL);
    }
      if (scan != S_SUCCESS)
    {
      return S_ERROR;
    }
      db_make_int (record_info[HEAP_RECORD_INFO_T_REPRID], or_rep_id (recdes));
      db_make_int (record_info[HEAP_RECORD_INFO_T_REPRID], or_chn (recdes));

      or_mvcc_get_header (recdes, &mvcc_header);
      db_make_bigint (record_info[HEAP_RECORD_INFO_T_MVCC_INSID], MVCC_GET_INSID (&mvcc_header));
      if (MVCC_IS_HEADER_DELID_VALID (&mvcc_header))
    {
      db_make_bigint (record_info[HEAP_RECORD_INFO_T_MVCC_DELID], MVCC_GET_DELID (&mvcc_header));
    }
      else
    {
      db_make_null (record_info[HEAP_RECORD_INFO_T_MVCC_DELID]);
    }
      db_make_int (record_info[HEAP_RECORD_INFO_T_CHN], OR_GET_MVCC_CHN (&mvcc_header));
      db_make_int (record_info[HEAP_RECORD_INFO_T_MVCC_FLAGS], MVCC_GET_FLAG (&mvcc_header));
      if (MVCC_IS_FLAG_SET (&mvcc_header, OR_MVCC_FLAG_VALID_PREV_VERSION))
    {
      db_make_int (record_info[HEAP_RECORD_INFO_T_MVCC_PREV_VERSION], 1);
    }
      else
    {
      db_make_int (record_info[HEAP_RECORD_INFO_T_MVCC_PREV_VERSION], 0);
    }
      break;
    case REC_RELOCATION:
    case REC_MARKDELETED:
    case REC_DELETED_WILL_REUSE:
    case REC_ASSIGN_ADDRESS:
    case REC_UNKNOWN:
    default:
      db_make_null (record_info[HEAP_RECORD_INFO_T_REPRID]);
      db_make_null (record_info[HEAP_RECORD_INFO_T_CHN]);
      db_make_null (record_info[HEAP_RECORD_INFO_T_MVCC_INSID]);
      db_make_null (record_info[HEAP_RECORD_INFO_T_MVCC_DELID]);
      db_make_null (record_info[HEAP_RECORD_INFO_T_MVCC_FLAGS]);

      db_make_int (record_info[HEAP_RECORD_INFO_T_MVCC_PREV_VERSION], 0);

      recdes->area_size = -1;
      recdes->data = NULL;
      if (scan_cache != NULL && scan_cache->cache_last_fix_page)
    {
      assert (PGBUF_IS_CLEAN_WATCHER (&(scan_cache->page_watcher)));
      if (page_watcher->pgptr != NULL)
        {
          pgbuf_replace_watcher (thread_p, page_watcher, &scan_cache->page_watcher);
        }
    }
      else if (page_watcher->pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, page_watcher);
    }
      break;
    }

  return scan;
}

/*
 * heap_next () - Retrieve or peek next object
 *   return: SCAN_CODE (Either of S_SUCCESS, S_DOESNT_FIT, S_END, S_ERROR)
 *   hfid(in):
 *   class_oid(in):
 *   next_oid(in/out): Object identifier of current record.
 *                     Will be set to next available record or NULL_OID when
 *                     there is not one.
 *   recdes(in/out): Pointer to a record descriptor. Will be modified to
 *                   describe the new record.
 *   scan_cache(in/out): Scan cache or NULL
 *   ispeeking(in): PEEK when the object is peeked, scan_cache cannot be NULL
 *                  COPY when the object is copied
 *
 */
SCAN_CODE
heap_next (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, OID * next_oid, RECDES * recdes,
       HEAP_SCANCACHE * scan_cache, int ispeeking)
{
  return heap_next_internal (thread_p, hfid, class_oid, next_oid, recdes, scan_cache, ispeeking, false, NULL);
}

/*
 * heap_next_record_info () - Retrieve or peek next object.
 *
 * return            : SCAN_CODE.
 * thread_p (in)         : Thread entry.
 * hfid (in)             : Heap file identifier.
 * class_oid (in)        : Class Object identifier.
 * next_oid (in/out)         : Current object identifier. Will store the next
 *                 scanned object identifier.
 * recdes (in)           : Record descriptor.
 * scan_cache (in)       : Scan cache.
 * ispeeking (in)        : PEEK/COPY.
 * cache_recordinfo (in/out) : DB_VALUE pointer array that caches record
 *                 information values.
 *
 * NOTE: This function is similar to heap next. The difference is that all
 *   slots are scanned in their order in the heap file and along with
 *   record data also information about that record is obtained.
 */
SCAN_CODE
heap_next_record_info (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, OID * next_oid, RECDES * recdes,
               HEAP_SCANCACHE * scan_cache, int ispeeking, DB_VALUE ** cache_recordinfo)
{
  return heap_next_internal (thread_p, hfid, class_oid, next_oid, recdes, scan_cache, ispeeking, false,
                 cache_recordinfo);
}

/*
 * heap_prev () - Retrieve or peek next object
 *   return: SCAN_CODE (Either of S_SUCCESS, S_DOESNT_FIT, S_END, S_ERROR)
 *   hfid(in):
 *   class_oid(in):
 *   next_oid(in/out): Object identifier of current record.
 *                     Will be set to next available record or NULL_OID when
 *                     there is not one.
 *   recdes(in/out): Pointer to a record descriptor. Will be modified to
 *                   describe the new record.
 *   scan_cache(in/out): Scan cache or NULL
 *   ispeeking(in): PEEK when the object is peeked, scan_cache cannot be NULL
 *                  COPY when the object is copied
 *
 */
SCAN_CODE
heap_prev (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, OID * next_oid, RECDES * recdes,
       HEAP_SCANCACHE * scan_cache, int ispeeking)
{
  return heap_next_internal (thread_p, hfid, class_oid, next_oid, recdes, scan_cache, ispeeking, true, NULL);
}

/*
 * heap_prev_record_info () - Retrieve or peek next object.
 *
 * return            : SCAN_CODE.
 * thread_p (in)         : Thread entry.
 * hfid (in)             : Heap file identifier.
 * class_oid (in)        : Class Object identifier.
 * prev_oid (in/out)         : Current object identifier. Will store the
 *                 previous scanned object identifier.
 * recdes (in)           : Record descriptor.
 * scan_cache (in)       : Scan cache.
 * ispeeking (in)        : PEEK/COPY.
 * cache_recordinfo (in/out) : DB_VALUE pointer array that caches record
 *                 information values
 *
 * NOTE: This function is similar to heap next. The difference is that all
 *   slots are scanned in their order in the heap file and along with
 *   record data also information about that record is obtained.
 */
SCAN_CODE
heap_prev_record_info (THREAD_ENTRY * thread_p, const HFID * hfid, OID * class_oid, OID * next_oid, RECDES * recdes,
               HEAP_SCANCACHE * scan_cache, int ispeeking, DB_VALUE ** cache_recordinfo)
{
  return heap_next_internal (thread_p, hfid, class_oid, next_oid, recdes, scan_cache, ispeeking, true,
                 cache_recordinfo);
}

/*
 * heap_scancache_start_chain_update  () - start new scan cache for MVCC
 *                    chain update
 *   return: error code
 *   thread_p(in): thread entry
 *   new_scan_cache(in/out): the new scan cache
 *   old_scan_cache(in/out): the old scan cache
 *   next_row_version(in): next row version
 *
 * Note: This function start a new scan cache used to update
 *  MVCC chain. The old and new scan cache may share common data.
 */
int
heap_scancache_start_chain_update (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * new_scan_cache,
                   HEAP_SCANCACHE * old_scan_cache, OID * next_row_version)
{
  assert (new_scan_cache != NULL);
  assert (old_scan_cache != NULL);

  /* update scan cache */

  /* start a local cache that is suitable for our needs */
  if (heap_scancache_start (thread_p, new_scan_cache, &old_scan_cache->node.hfid, &old_scan_cache->node.class_oid,
                true, false, NULL) != NO_ERROR)
    {
      /* TODO - er_set */
      return ER_FAILED;
    }

  /* use current_scan_cache->area in order to alloc only once */
  new_scan_cache->area = old_scan_cache->area;
  new_scan_cache->area_size = old_scan_cache->area_size;
  /* set pgptr if is the case */
  if (old_scan_cache->page_watcher.pgptr != NULL)
    {
      /* handle this case, just to be sure */
      VPID *vpidptr_incache;
      VPID vpid;

      vpid.volid = next_row_version->volid;
      vpid.pageid = next_row_version->pageid;
      vpidptr_incache = pgbuf_get_vpid_ptr (old_scan_cache->page_watcher.pgptr);
      if (VPID_EQ (&vpid, vpidptr_incache))
    {
      pgbuf_replace_watcher (thread_p, &old_scan_cache->page_watcher, &new_scan_cache->page_watcher);
    }
      else
    {
      /* Free the previous scan page */
      pgbuf_ordered_unfix (thread_p, &old_scan_cache->page_watcher);
    }
    }

  return NO_ERROR;
}

/*
 * heap_get_mvcc_rec_header_from_overflow () - Get record header from overflow
 *                         page.
 *
 * return :
 * PAGE_PTR ovf_page (in) : overflow page pointer
 * MVCC_REC_HEADER * mvcc_header (in/out) : MVCC record header
 * recdes(in/out): if not NULL then receives first overflow page
 */
int
heap_get_mvcc_rec_header_from_overflow (PAGE_PTR ovf_page, MVCC_REC_HEADER * mvcc_header, RECDES * peek_recdes)
{
  RECDES ovf_recdes;

  assert (ovf_page != NULL);
  assert (mvcc_header != NULL);

  if (peek_recdes == NULL)
    {
      peek_recdes = &ovf_recdes;
    }
  peek_recdes->data = overflow_get_first_page_data (ovf_page);
  peek_recdes->length = OR_MVCC_MAX_HEADER_SIZE;

  return or_mvcc_get_header (peek_recdes, mvcc_header);
}

/*
 * heap_set_mvcc_rec_header_on_overflow () - Updates MVCC record header on
 *                       overflow page data.
 *
 * return       : Void.
 * ovf_page (in)    : First overflow page.
 * mvcc_header (in) : MVCC Record header.
 */
int
heap_set_mvcc_rec_header_on_overflow (PAGE_PTR ovf_page, MVCC_REC_HEADER * mvcc_header)
{
  RECDES ovf_recdes;

  assert (ovf_page != NULL);
  assert (mvcc_header != NULL);

  ovf_recdes.data = overflow_get_first_page_data (ovf_page);
  ovf_recdes.area_size = ovf_recdes.length = OR_HEADER_SIZE (ovf_recdes.data);
  /* Safe guard */
  assert (ovf_recdes.length == OR_MVCC_MAX_HEADER_SIZE);

  /* Make sure the header has maximum size for overflow records */
  if (!MVCC_IS_FLAG_SET (mvcc_header, OR_MVCC_FLAG_VALID_INSID))
    {
      /* Add MVCCID_ALL_VISIBLE for insert MVCCID */
      MVCC_SET_FLAG_BITS (mvcc_header, OR_MVCC_FLAG_VALID_INSID);
      MVCC_SET_INSID (mvcc_header, MVCCID_ALL_VISIBLE);
    }

  if (!MVCC_IS_FLAG_SET (mvcc_header, OR_MVCC_FLAG_VALID_DELID))
    {
      /* Add MVCCID_NULL for delete MVCCID */
      MVCC_SET_FLAG_BITS (mvcc_header, OR_MVCC_FLAG_VALID_DELID);
      MVCC_SET_DELID (mvcc_header, MVCCID_NULL);
    }

  /* Safe guard */
  assert (mvcc_header_size_lookup[MVCC_GET_FLAG (mvcc_header)] == OR_MVCC_MAX_HEADER_SIZE);
  return or_mvcc_set_header (&ovf_recdes, mvcc_header);
}

/*
 * heap_get_bigone_content () - get content of a big record
 *
 * return       : scan code.
 * thread_p (in)    :
 * scan_cache (in)  : Scan cache
 * ispeeking(in)    : 0 if the content will be copied.
 * forward_oid(in)  : content oid.
 * recdes(in/out)   : record descriptor that will contain its content
 */
SCAN_CODE
heap_get_bigone_content (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, bool ispeeking, OID * forward_oid,
             RECDES * recdes)
{
  SCAN_CODE scan = S_SUCCESS;

  /* Try to reuse the previously allocated area No need to check the snapshot since was already checked */
  if (scan_cache != NULL && (ispeeking == PEEK || recdes->data == NULL || recdes->data == scan_cache->area))
    {
      if (scan_cache->area == NULL)
    {
      /* 
       * Allocate an area to hold the object. Assume that the object will fit in two pages for not better estimates.
       * We could call heap_ovf_get_length, but it may be better to just guess and realloc if needed.
       * We could also check the estimates for average object length, but again, it may be expensive and may not be
       * accurate for this object.
       */
      scan_cache->area_size = DB_PAGESIZE * 2;
      scan_cache->area = (char *) db_private_alloc (thread_p, scan_cache->area_size);
      if (scan_cache->area == NULL)
        {
          scan_cache->area_size = -1;
          return S_ERROR;
        }
    }
      recdes->data = scan_cache->area;
      recdes->area_size = scan_cache->area_size;

      while ((scan = heap_ovf_get (thread_p, forward_oid, recdes, NULL_CHN, NULL)) == S_DOESNT_FIT)
    {
      /* 
       * The object did not fit into such an area, reallocate a new
       * area
       */

      recdes->area_size = -recdes->length;
      recdes->data = (char *) db_private_realloc (thread_p, scan_cache->area, recdes->area_size);
      if (recdes->data == NULL)
        {
          return S_ERROR;
        }
      scan_cache->area_size = recdes->area_size;
      scan_cache->area = recdes->data;
    }
      if (scan != S_SUCCESS)
    {
      recdes->data = NULL;
    }
    }
  else
    {
      scan = heap_ovf_get (thread_p, forward_oid, recdes, NULL_CHN, NULL);
    }

  return scan;
}

/*
 * heap_get_class_oid_from_page () - Gets heap page owner class OID.
 *
 * return      : Error code.
 * thread_p (in)   : Thread entry.
 * page_p (in)     : Heap page.
 * class_oid (out) : Class identifier.
 */
int
heap_get_class_oid_from_page (THREAD_ENTRY * thread_p, PAGE_PTR page_p, OID * class_oid)
{
  RECDES chain_recdes;
  HEAP_CHAIN *chain;

  if (spage_get_record (thread_p, page_p, HEAP_HEADER_AND_CHAIN_SLOTID, &chain_recdes, PEEK) != S_SUCCESS)
    {
      assert (0);
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      return ER_FAILED;
    }

  chain = (HEAP_CHAIN *) chain_recdes.data;
  COPY_OID (class_oid, &(chain->class_oid));

  /* 
   * kludge, root class is identified with a NULL class OID but we must
   * substitute the actual OID here - think about this
   */
  if (OID_ISNULL (class_oid))
    {
      /* root class class oid, substitute with global */
      COPY_OID (class_oid, oid_Root_class_oid);
    }
  return NO_ERROR;
}

/*
 * heap_mvcc_log_home_change_on_delete () - Log the change of record in home page when MVCC delete does not
 *                      change a REC_HOME to REC_HOME.
 *
 * return      : Void.
 * thread_p (in)   : Thread entry.
 * old_recdes (in) : NULL or a REC_RELOCATION record.
 * new_recdes (in) : Record including delete info (MVCCID and next version).
 * p_addr (in)     : Log data address.
 */
static void
heap_mvcc_log_home_change_on_delete (THREAD_ENTRY * thread_p, RECDES * old_recdes, RECDES * new_recdes,
                     LOG_DATA_ADDR * p_addr)
{
  HEAP_PAGE_VACUUM_STATUS vacuum_status = heap_page_get_vacuum_status (thread_p, p_addr->pgptr);

  /* REC_RELOCATION type record was brought back to home page or REC_HOME has been converted to
   * REC_RELOCATION/REC_BIGONE. */

  /* Update heap chain for vacuum. */
  heap_page_update_chain_after_mvcc_op (thread_p, p_addr->pgptr, logtb_get_current_mvccid (thread_p));
  if (heap_page_get_vacuum_status (thread_p, p_addr->pgptr) != vacuum_status)
    {
      /* Mark vacuum status change for recovery. */
      p_addr->offset |= HEAP_RV_FLAG_VACUUM_STATUS_CHANGE;
    }

  log_append_undoredo_recdes (thread_p, RVHF_MVCC_DELETE_MODIFY_HOME, p_addr, old_recdes, new_recdes);
}

/*
 * heap_mvcc_log_home_no_change () - Update page chain for vacuum and notify vacuum even when home page is not changed.
 *                   Used by update/delete of REC_RELOCATION and REC_BIGONE.
 *
 * return    : Void.
 * thread_p (in) : Thread entry.
 * p_addr (in)   : Data address for logging.
 */
static void
heap_mvcc_log_home_no_change (THREAD_ENTRY * thread_p, LOG_DATA_ADDR * p_addr)
{
  HEAP_PAGE_VACUUM_STATUS vacuum_status = heap_page_get_vacuum_status (thread_p, p_addr->pgptr);

  /* Update heap chain for vacuum. */
  heap_page_update_chain_after_mvcc_op (thread_p, p_addr->pgptr, logtb_get_current_mvccid (thread_p));
  if (vacuum_status != heap_page_get_vacuum_status (thread_p, p_addr->pgptr))
    {
      /* Mark vacuum status change for recovery. */
      p_addr->offset |= HEAP_RV_FLAG_VACUUM_STATUS_CHANGE;
    }

  log_append_undoredo_data (thread_p, RVHF_MVCC_NO_MODIFY_HOME, p_addr, 0, 0, NULL, NULL);
}

/*
 * heap_rv_redo_update_and_update_chain () - Redo update record as part of MVCC delete operation.
 *   return: int
 *   rcv(in): Recovery structure
 */
int
heap_rv_redo_update_and_update_chain (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  int error_code = NO_ERROR;
  bool vacuum_status_change = false;
  PGSLOTID slotid;

  assert (rcv->pgptr != NULL);
  assert (MVCCID_IS_NORMAL (rcv->mvcc_id));

  slotid = rcv->offset;
  if (slotid & HEAP_RV_FLAG_VACUUM_STATUS_CHANGE)
    {
      vacuum_status_change = true;
    }
  slotid = slotid & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
  assert (slotid > 0);

  error_code = heap_rv_redo_update (thread_p, rcv);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }

  heap_page_rv_chain_update (thread_p, rcv->pgptr, rcv->mvcc_id, vacuum_status_change);
  /* Page was already marked as dirty */
  return NO_ERROR;
}

/*
 * heap_attrinfo_check_unique_index () - check whether exists an unique index on
 *                  specified attributes
 *   return: true, if there is an index containing specified attributes
 *   thread_p(in): thread entry
 *   attr_info(in): attribute info
 *   att_id(in): attribute ids
 *   n_att_id(in): count attributes
 */
bool
heap_attrinfo_check_unique_index (THREAD_ENTRY * thread_p, HEAP_CACHE_ATTRINFO * attr_info, ATTR_ID * att_id,
                  int n_att_id)
{
  OR_INDEX *index;
  int num_btids, i, j, k;

  if (attr_info == NULL || att_id == NULL)
    {
      return false;
    }

  num_btids = attr_info->last_classrepr->n_indexes;
  for (i = 0; i < num_btids; i++)
    {
      index = &(attr_info->last_classrepr->indexes[i]);
      if (btree_is_unique_type (index->type))
    {
      for (j = 0; j < n_att_id; j++)
        {
          for (k = 0; k < index->n_atts; k++)
        {
          if (att_id[j] == (ATTR_ID) (index->atts[k]->id))
            {       /* the index key_type has updated attr */
              return true;
            }
        }
        }
    }
    }

  return false;
}

#if defined(ENABLE_UNUSED_FUNCTION)
/*
 * heap_try_fetch_header_page () -
 *                  try to fetch header page, having home page already fetched
 *
 *   return: error code
 *   thread_p(in): thread entry
 *   home_pgptr_p(out):
 *   home_vpid_p(in):
 *   oid_p(in):
 *   hdr_pgptr_p(out):
 *   hdr_vpid_p(in):
 *   scan_cache(in):
 *   again_count_p(in/out):
 *   again_max(in):
 */
/* TODO - fix er_clear */
STATIC_INLINE int
heap_try_fetch_header_page (THREAD_ENTRY * thread_p, PAGE_PTR * home_pgptr_p, const VPID * home_vpid_p,
                const OID * oid_p, PAGE_PTR * hdr_pgptr_p, const VPID * hdr_vpid_p,
                HEAP_SCANCACHE * scan_cache, int *again_count_p, int again_max)
{
  int error_code = NO_ERROR;

  *hdr_pgptr_p = pgbuf_fix (thread_p, hdr_vpid_p, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_CONDITIONAL_LATCH);
  if (*hdr_pgptr_p != NULL)
    {
      return NO_ERROR;
    }

  pgbuf_unfix_and_init (thread_p, *home_pgptr_p);
  *hdr_pgptr_p = heap_scan_pb_lock_and_fetch (thread_p, hdr_vpid_p, OLD_PAGE, X_LOCK, scan_cache, NULL);
  if (*hdr_pgptr_p == NULL)
    {
      error_code = er_errid ();
      if (error_code == ER_PB_BAD_PAGEID)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, hdr_vpid_p->volid, hdr_vpid_p->pageid,
          0);
      error_code = ER_HEAP_UNKNOWN_OBJECT;
    }
    }
  else
    {
      *home_pgptr_p = pgbuf_fix (thread_p, home_vpid_p, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_CONDITIONAL_LATCH);
      if (*home_pgptr_p == NULL)
    {
      pgbuf_unfix_and_init (thread_p, *hdr_pgptr_p);
      if ((*again_count_p)++ >= again_max)
        {
          error_code = er_errid ();
          if (error_code == ER_PB_BAD_PAGEID)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, oid_p->volid, oid_p->pageid,
              oid_p->slotid);
          error_code = ER_HEAP_UNKNOWN_OBJECT;
        }
          else if (error_code == NO_ERROR)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PAGE_LATCH_ABORTED, 2, home_vpid_p->volid,
              home_vpid_p->pageid);
          error_code = ER_PAGE_LATCH_ABORTED;
        }
        }
    }
    }

  return error_code;
}

/*
 * heap_try_fetch_forward_page () -
 *                  try to fetch forward page, having home page already fetched
 *
 *   return: error code
 *   thread_p(in): thread entry
 *   home_pgptr_p(out):
 *   home_vpid_p(in):
 *   oid_p(in):
 *   fwd_pgptr_p(out):
 *   fwd_vpid_p(in):
 *   fwd_oid_p(in):
 *   scan_cache(in):
 *   again_count_p(in/out):
 *   again_max(in):
 */
STATIC_INLINE int
heap_try_fetch_forward_page (THREAD_ENTRY * thread_p, PAGE_PTR * home_pgptr_p, const VPID * home_vpid_p,
                 const OID * oid_p, PAGE_PTR * fwd_pgptr_p, const VPID * fwd_vpid_p, const OID * fwd_oid_p,
                 HEAP_SCANCACHE * scan_cache, int *again_count_p, int again_max)
{
  int error_code = NO_ERROR;

  *fwd_pgptr_p = pgbuf_fix (thread_p, fwd_vpid_p, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_CONDITIONAL_LATCH);
  if (*fwd_pgptr_p != NULL)
    {
      return NO_ERROR;
    }

  pgbuf_unfix_and_init (thread_p, *home_pgptr_p);
  *fwd_pgptr_p = heap_scan_pb_lock_and_fetch (thread_p, fwd_vpid_p, OLD_PAGE, X_LOCK, scan_cache, NULL);
  if (*fwd_pgptr_p == NULL)
    {
      error_code = er_errid ();
      if (error_code == ER_PB_BAD_PAGEID)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, fwd_oid_p->volid, fwd_oid_p->pageid,
          fwd_oid_p->slotid);
      error_code = ER_HEAP_UNKNOWN_OBJECT;
    }
    }
  else
    {
      *home_pgptr_p = pgbuf_fix (thread_p, home_vpid_p, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_CONDITIONAL_LATCH);
      if (*home_pgptr_p == NULL)
    {
      pgbuf_unfix_and_init (thread_p, *fwd_pgptr_p);
      if ((*again_count_p)++ >= again_max)
        {
          error_code = er_errid ();
          if (error_code == ER_PB_BAD_PAGEID)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, oid_p->volid, oid_p->pageid,
              oid_p->slotid);
          error_code = ER_HEAP_UNKNOWN_OBJECT;
        }
          else if (error_code == NO_ERROR)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PAGE_LATCH_ABORTED, 2, home_vpid_p->volid,
              home_vpid_p->pageid);
          error_code = ER_PAGE_LATCH_ABORTED;
        }
        }
    }
    }

  return error_code;
}

/*
 * heap_try_fetch_header_with_forward_page () -
 *       try to fetch header and forward page, having home page already fetched
 *
 *   return: error code
 *   thread_p(in): thread entry
 *   home_pgptr_p(out):
 *   home_vpid_p(in):
 *   oid_p(in):
 *   hdr_pgptr_p(out):
 *   hdr_vpid_p(in):
 *   fwd_pgptr_p(out):
 *   fwd_vpid_p(in):
 *   fwd_oid_p(in):
 *   scan_cache(in):
 *   again_count_p(in/out):
 *   again_max(in):
 */
STATIC_INLINE int
heap_try_fetch_header_with_forward_page (THREAD_ENTRY * thread_p, PAGE_PTR * home_pgptr_p, const VPID * home_vpid_p,
                     const OID * oid_p, PAGE_PTR * hdr_pgptr_p, const VPID * hdr_vpid_p,
                     PAGE_PTR * fwd_pgptr_p, const VPID * fwd_vpid_p, const OID * fwd_oid_p,
                     HEAP_SCANCACHE * scan_cache, int *again_count_p, int again_max)
{
  int error_code = NO_ERROR;

  *hdr_pgptr_p = pgbuf_fix (thread_p, hdr_vpid_p, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_CONDITIONAL_LATCH);
  if (*hdr_pgptr_p != NULL)
    {
      return NO_ERROR;
    }

  pgbuf_unfix_and_init (thread_p, *home_pgptr_p);
  pgbuf_unfix_and_init (thread_p, *fwd_pgptr_p);
  *hdr_pgptr_p = heap_scan_pb_lock_and_fetch (thread_p, hdr_vpid_p, OLD_PAGE, X_LOCK, scan_cache, NULL);
  if (*hdr_pgptr_p == NULL)
    {
      error_code = er_errid ();
      if (error_code == ER_PB_BAD_PAGEID)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, hdr_vpid_p->volid, hdr_vpid_p->pageid,
          0);
      error_code = ER_HEAP_UNKNOWN_OBJECT;
    }
    }
  else
    {
      *home_pgptr_p = pgbuf_fix (thread_p, home_vpid_p, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_CONDITIONAL_LATCH);
      if (*home_pgptr_p == NULL)
    {
      pgbuf_unfix_and_init (thread_p, *hdr_pgptr_p);
      if ((*again_count_p)++ >= again_max)
        {
          error_code = er_errid ();
          if (error_code == ER_PB_BAD_PAGEID)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, oid_p->volid, oid_p->pageid,
              oid_p->slotid);
          error_code = ER_HEAP_UNKNOWN_OBJECT;
        }
          else if (error_code == NO_ERROR)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PAGE_LATCH_ABORTED, 2, home_vpid_p->volid,
              home_vpid_p->pageid);
          error_code = ER_PAGE_LATCH_ABORTED;
        }
        }
    }
      else
    {
      *fwd_pgptr_p = pgbuf_fix (thread_p, fwd_vpid_p, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_CONDITIONAL_LATCH);
      if (*fwd_pgptr_p == NULL)
        {
          pgbuf_unfix_and_init (thread_p, *hdr_pgptr_p);
          pgbuf_unfix_and_init (thread_p, *home_pgptr_p);
          if ((*again_count_p)++ >= again_max)
        {
          error_code = er_errid ();
          if (error_code == ER_PB_BAD_PAGEID)
            {
              er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, fwd_oid_p->volid,
                  fwd_oid_p->pageid, fwd_oid_p->slotid);
              error_code = ER_HEAP_UNKNOWN_OBJECT;
            }
          else if (er_errid () == NO_ERROR)
            {
              er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PAGE_LATCH_ABORTED, 2, fwd_vpid_p->volid,
                  fwd_vpid_p->pageid);
            }
        }
        }
    }
    }

  return error_code;
}
#endif /* ENABLE_UNUSED_FUNCTION */

/*
 * heap_get_header_page () -
 *   return: error code
 *   btid(in): Heap file identifier
 *   header_vpid(out):
 *
 * Note: get the page identifier of the first allocated page of the given file.
 */
int
heap_get_header_page (THREAD_ENTRY * thread_p, const HFID * hfid, VPID * header_vpid)
{
  assert (!VFID_ISNULL (&hfid->vfid));

  return file_get_sticky_first_page (thread_p, &hfid->vfid, header_vpid);
}

/*
 * heap_scancache_quick_start_root_hfid () - Start caching information for a
 *                       heap scan on root hfid
 *   return: NO_ERROR
 *   thread_p(in):
 *   scan_cache(in/out): Scan cache
 *
 * Note: this is similar to heap_scancache_quick_start, except it sets the
 *   HFID of root in the scan_cache (otherwise remains NULL).
 *   This should be used to avoid inconsistency when using ordered fix.
 */
int
heap_scancache_quick_start_root_hfid (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache)
{
  HFID root_hfid;

  (void) boot_find_root_heap (&root_hfid);
  (void) heap_scancache_quick_start_internal (scan_cache, &root_hfid);
  scan_cache->page_latch = S_LOCK;

  return NO_ERROR;
}


/*
 * heap_scancache_quick_start_with_class_oid () - Start caching information for
 *                         a heap scan on a class.
 *
 *   return: NO_ERROR
 *   thread_p(in):
 *   scan_cache(in/out): Scan cache
 *   class_oid(in): class
 *
 * Note: this is similar to heap_scancache_quick_start, except it sets the
 *   HFID of class in the scan_cache (otherwise remains NULL).
 *   This should be used to avoid inconsistency when using ordered fix.
 *   This has a page latch overhead on top of heap_scancache_quick_start.
 *
 */
int
heap_scancache_quick_start_with_class_oid (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, OID * class_oid)
{
  HFID class_hfid;

  heap_get_hfid_from_class_oid (thread_p, class_oid, &class_hfid);
  (void) heap_scancache_quick_start_with_class_hfid (thread_p, scan_cache, &class_hfid);
  scan_cache->page_latch = S_LOCK;

  return NO_ERROR;
}

/*
 * heap_scancache_quick_start_with_class_hfid () - Start caching information for
 *                         a heap scan on a class.
 *
 *   return: NO_ERROR
 *   thread_p(in):
 *   scan_cache(in/out): Scan cache
 *   class_oid(in): class
 *
 * Note: this is similar to heap_scancache_quick_start, except it sets the
 *   HFID of class in the scan_cache (otherwise remains NULL).
 *   This should be used to avoid inconsistency when using ordered fix.
 *
 */
int
heap_scancache_quick_start_with_class_hfid (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, const HFID * hfid)
{
  (void) heap_scancache_quick_start_internal (scan_cache, hfid);
  scan_cache->page_latch = S_LOCK;

  return NO_ERROR;
}


/*
 * heap_scancache_quick_start_modify_with_class_oid () -
 *          Start caching information for a heap scan on class.
 *
 *   return: NO_ERROR
 *   thread_p(in):
 *   scan_cache(in/out): Scan cache
 *   class_oid(in): class
 *
 * Note: this is similar to heap_scancache_quick_start_modify, except it sets
 *   the HFID of class in the scan_cache (otherwise remains NULL).
 *   This should be used to avoid inconsistency when using ordered fix.
 *   This has a page latch overhead on top of heap_scancache_quick_start.
 */
int
heap_scancache_quick_start_modify_with_class_oid (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, OID * class_oid)
{
  HFID class_hfid;

  heap_get_hfid_from_class_oid (thread_p, class_oid, &class_hfid);
  (void) heap_scancache_quick_start_internal (scan_cache, &class_hfid);
  scan_cache->page_latch = X_LOCK;

  return NO_ERROR;
}

/*
 * heap_link_watchers () - link page watchers of a child operation to it's
 *             parent
 *   child(in): child operation context
 *   parent(in): parent operation context
 *
 * NOTE: Sometimes, parts of a heap operation are executed in a parent heap
 *       operation, skipping the fixing of pages and location of records.
 *       Since page watchers are identified by address, we must use a single
 *       location for them, and reference it everywhere.
 */
static void
heap_link_watchers (HEAP_OPERATION_CONTEXT * child, HEAP_OPERATION_CONTEXT * parent)
{
  assert (child != NULL);
  assert (parent != NULL);

  child->header_page_watcher_p = &parent->header_page_watcher;
  child->forward_page_watcher_p = &parent->forward_page_watcher;
  child->overflow_page_watcher_p = &parent->overflow_page_watcher;
  child->home_page_watcher_p = &parent->home_page_watcher;
}

/*
 * heap_unfix_watchers () - unfix context pages
 *   thread_p(in): thread entry
 *   context(in): operation context
 *
 * NOTE: This function only unfixes physical watchers. Calling this in a child
 *       operation that was linked to the parent with heap_link_watchers will
 *       have no effect on the fixed pages.
 */
static void
heap_unfix_watchers (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  assert (context != NULL);

  /* unfix pages */
  if (context->home_page_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &context->home_page_watcher);
    }
  if (context->overflow_page_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &context->overflow_page_watcher);
    }
  if (context->header_page_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &context->header_page_watcher);
    }
  if (context->forward_page_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &context->forward_page_watcher);
    }
}

/*
 * heap_clear_operation_context () - clear a heap operation context
 *   context(in): the context
 *   hfid_p(in): heap file identifier
 */
static void
heap_clear_operation_context (HEAP_OPERATION_CONTEXT * context, HFID * hfid_p)
{
  assert (context != NULL);
  assert (hfid_p != NULL);

  /* keep hfid */
  HFID_COPY (&context->hfid, hfid_p);

  /* initialize watchers to HFID */
  PGBUF_INIT_WATCHER (&context->home_page_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid_p);
  PGBUF_INIT_WATCHER (&context->forward_page_watcher, PGBUF_ORDERED_HEAP_NORMAL, hfid_p);
  PGBUF_INIT_WATCHER (&context->overflow_page_watcher, PGBUF_ORDERED_HEAP_OVERFLOW, hfid_p);
  PGBUF_INIT_WATCHER (&context->header_page_watcher, PGBUF_ORDERED_HEAP_HDR, hfid_p);

  /* by default link physical watchers to usage watchers on same context */
  heap_link_watchers (context, context);

  /* nullify everything else */
  context->type = HEAP_OPERATION_NONE;
  context->update_in_place = UPDATE_INPLACE_NONE;
  OID_SET_NULL (&context->oid);
  OID_SET_NULL (&context->class_oid);
  context->recdes_p = NULL;
  context->scan_cache_p = NULL;

  context->map_recdes.data = NULL;
  context->map_recdes.length = 0;
  context->map_recdes.area_size = 0;
  context->map_recdes.type = REC_UNKNOWN;

  OID_SET_NULL (&context->ovf_oid);

  context->home_recdes.data = NULL;
  context->home_recdes.length = 0;
  context->home_recdes.area_size = 0;
  context->home_recdes.type = REC_UNKNOWN;

  context->record_type = REC_UNKNOWN;
  context->file_type = FILE_UNKNOWN_TYPE;
  OID_SET_NULL (&context->res_oid);
  context->is_logical_old = false;
  context->is_redistribute_insert_with_delid = false;

  context->time_track = NULL;
}

/*
 * heap_mark_class_as_modified () - add to transaction's modified class list
 *                                  and cache/decache coherency number
 *   thread_p(in): thread entry
 *   oid_p(in): class OID
 *   chn(in): coherency number (required iff decache == false)
 *   decache(in): (false => cache, true => decache)
 */
static int
heap_mark_class_as_modified (THREAD_ENTRY * thread_p, OID * oid_p, int chn, bool decache)
{
  char *classname = NULL;

  assert (oid_p != NULL);

  if (heap_Guesschn == NULL || HFID_IS_NULL (&(heap_Classrepr->rootclass_hfid)))
    {
      /* nothing to do */
      return NO_ERROR;
    }

  if (heap_get_class_name (thread_p, oid_p, &classname) != NO_ERROR || classname == NULL)
    {
      ASSERT_ERROR ();
      return ER_FAILED;
    }
  if (log_add_to_modified_class_list (thread_p, classname, oid_p) != NO_ERROR)
    {
      free_and_init (classname);
      return ER_FAILED;
    }

  free_and_init (classname);

  if (csect_enter (thread_p, CSECT_HEAP_CHNGUESS, INF_WAIT) != NO_ERROR)
    {
      return ER_FAILED;
    }
  heap_Guesschn->schema_change = true;

  if (decache)
    {
      (void) heap_chnguess_decache (oid_p);
    }
  else
    {
      (void) heap_chnguess_put (thread_p, oid_p, LOG_FIND_THREAD_TRAN_INDEX (thread_p), chn);
    }

  csect_exit (thread_p, CSECT_HEAP_CHNGUESS);

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_get_file_type () - get the file type from a heap operation context
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   returns: file type
 */
static FILE_TYPE
heap_get_file_type (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  FILE_TYPE file_type;
  if (context->scan_cache_p != NULL)
    {
      assert (HFID_EQ (&context->hfid, &context->scan_cache_p->node.hfid));
      assert (context->scan_cache_p->file_type != FILE_UNKNOWN_TYPE);

      return context->scan_cache_p->file_type;
    }
  else
    {
      if (heap_get_hfid_and_file_type_from_class_oid (thread_p, &context->class_oid, NULL, &file_type) != NO_ERROR)
    {
      ASSERT_ERROR ();
      return FILE_UNKNOWN_TYPE;
    }
      assert (file_type == FILE_HEAP || file_type == FILE_HEAP_REUSE_SLOTS);
      return file_type;
    }
}

/*
 * heap_is_valid_oid () - check if provided OID is valid
 *   oid_p(in): object identifier
 *   returns: error code or NO_ERROR
 */
static int
heap_is_valid_oid (THREAD_ENTRY * thread_p, OID * oid_p)
{
  DISK_ISVALID oid_valid = HEAP_ISVALID_OID (thread_p, oid_p);

  if (oid_valid != DISK_VALID)
    {
      if (oid_valid != DISK_ERROR)
    {
      assert (false);
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, oid_p->volid, oid_p->pageid,
          oid_p->slotid);
    }
      return ER_FAILED;
    }
  else
    {
      return NO_ERROR;
    }
}

/*
 * heap_fix_header_page () - fix header page for a heap operation context
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   returns: error code or NO_ERROR
 */
static int
heap_fix_header_page (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  VPID header_vpid;
  int rc;

  assert (context != NULL);
  assert (context->header_page_watcher_p != NULL);

  if (context->header_page_watcher_p->pgptr != NULL)
    {
      /* already fixed */
      return NO_ERROR;
    }

  /* fix header page */
  header_vpid.volid = context->hfid.vfid.volid;
  header_vpid.pageid = context->hfid.hpgid;

  /* fix page */
  rc = pgbuf_ordered_fix (thread_p, &header_vpid, OLD_PAGE, PGBUF_LATCH_WRITE, context->header_page_watcher_p);
  if (rc != NO_ERROR)
    {
      if (rc == ER_LK_PAGE_TIMEOUT && er_errid () == NO_ERROR)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PAGE_LATCH_ABORTED, 2, header_vpid.volid, header_vpid.pageid);
      rc = ER_PAGE_LATCH_ABORTED;
    }
      return rc;
    }

  /* check page type */
  (void) pgbuf_check_page_ptype (thread_p, context->header_page_watcher_p->pgptr, PAGE_HEAP);

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_fix_forward_page () - fix forward page for a heap operation context
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   forward_oid_hint(in): location of forward object (if known)
 *   returns: error code or NO_ERROR
 *
 * NOTE: If forward_oid_hint is provided, this function will fix it's page. If
 *       not, the function will treat the context's home_recdes as a forwarding
 *       record descriptor and read the identifier from it.
 */
static int
heap_fix_forward_page (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, OID * forward_oid_hint)
{
  VPID forward_vpid;
  OID forward_oid;
  int rc;

  assert (context != NULL);
  assert (context->forward_page_watcher_p != NULL);

  if (context->forward_page_watcher_p->pgptr != NULL)
    {
      /* already fixed */
      return NO_ERROR;
    }

  if (forward_oid_hint == NULL)
    {
      assert (context->home_recdes.data != NULL);

      /* cast home record as forward oid if no hint is provided */
      forward_oid = *((OID *) context->home_recdes.data);
    }
  else
    {
      /* oid is provided, use it */
      COPY_OID (&forward_oid, forward_oid_hint);
    }

  /* prepare VPID */
  forward_vpid.pageid = forward_oid.pageid;
  forward_vpid.volid = forward_oid.volid;

  /* fix forward page */
  PGBUF_WATCHER_COPY_GROUP (context->forward_page_watcher_p, context->home_page_watcher_p);
  rc = pgbuf_ordered_fix (thread_p, &forward_vpid, OLD_PAGE, PGBUF_LATCH_WRITE, context->forward_page_watcher_p);
  if (rc != NO_ERROR)
    {
      if (rc == ER_LK_PAGE_TIMEOUT && er_errid () == NO_ERROR)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PAGE_LATCH_ABORTED, 2, forward_vpid.volid, forward_vpid.pageid);
    }
      return ER_FAILED;
    }
  (void) pgbuf_check_page_ptype (thread_p, context->forward_page_watcher_p->pgptr, PAGE_HEAP);

#if defined(CUBRID_DEBUG)
  if (spage_get_record_type (context->forward_page_watcher_p->pgptr, forward_oid.slotid) != REC_NEWHOME)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_BAD_OBJECT_TYPE, 3, forward_oid.volid, forward_oid.pageid,
          forward_oid.slotid);
      return ER_FAILED;
    }
#endif

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_build_forwarding_recdes () - build a record descriptor for pointing to
 *                                   a forward object
 *   recdes_p(in): record descriptor to build into
 *   rec_type(in): type of record
 *   forward_oid(in): the oid where the forwarding record will point
 */
static void
heap_build_forwarding_recdes (RECDES * recdes_p, INT16 rec_type, OID * forward_oid)
{
  assert (recdes_p != NULL);
  assert (forward_oid != NULL);

  recdes_p->type = rec_type;
  recdes_p->data = (char *) forward_oid;

  recdes_p->length = sizeof (OID);
  recdes_p->area_size = sizeof (OID);
}

/*
 * heap_insert_adjust_recdes_header () - adjust record header for insert
 *                                       operation
 *   thread_p(in): thread entry
 *   insert_context(in/out): insert context
 *   is_mvcc_class(in): true, if MVCC class
 *   returns: error code or NO_ERROR
 *
 * NOTE: For MVCC class, it will add an insert_id to the header. For non-MVCC class, it will clear all flags.
 *   The function will alter the provided record descriptor data area.
 */
static int
heap_insert_adjust_recdes_header (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * insert_context, bool is_mvcc_class)
{
  MVCC_REC_HEADER mvcc_rec_header;
  int record_size;
  int repid_and_flag_bits = 0, mvcc_flags = 0;
  char *new_ins_mvccid_pos_p, *start_p, *existing_data_p;
  MVCCID mvcc_id;
  bool use_optimization = false;

  assert (insert_context != NULL);
  assert (insert_context->type == HEAP_OPERATION_INSERT);
  assert (insert_context->recdes_p != NULL);

  record_size = insert_context->recdes_p->length;

  repid_and_flag_bits = OR_GET_MVCC_REPID_AND_FLAG (insert_context->recdes_p->data);
  mvcc_flags = (repid_and_flag_bits >> OR_MVCC_FLAG_SHIFT_BITS) & OR_MVCC_FLAG_MASK;

#if defined (SERVER_MODE)
  /* In case of partitions, it is possible to have OR_MVCC_FLAG_VALID_PREV_VERSION flag. */
  use_optimization = (is_mvcc_class && (insert_context->update_in_place == UPDATE_INPLACE_NONE)
              && (!(mvcc_flags & OR_MVCC_FLAG_VALID_PREV_VERSION))
              && !heap_is_big_length (record_size + OR_MVCCID_SIZE));
#endif

  if (use_optimization)
    {
      /* 
       * Most common case. Since is UPDATE_INPLACE_NONE, the header does not have DELID.
       * Optimize header adjustment.
       */
      assert (!(mvcc_flags & OR_MVCC_FLAG_VALID_DELID));
      mvcc_id = logtb_get_current_mvccid (thread_p);

      start_p = insert_context->recdes_p->data;
      /* Skip bytes up to insid_offset */
      new_ins_mvccid_pos_p = start_p + OR_MVCC_INSERT_ID_OFFSET;

      if (!(mvcc_flags & OR_MVCC_FLAG_VALID_INSID))
    {
      /* Sets MVCC INSID flag, overwrite first four bytes. */
      repid_and_flag_bits |= (OR_MVCC_FLAG_VALID_INSID << OR_MVCC_FLAG_SHIFT_BITS);
      OR_PUT_INT (start_p, repid_and_flag_bits);

      /* Move the record data before inserting INSID */
      assert (insert_context->recdes_p->area_size >= insert_context->recdes_p->length + OR_MVCCID_SIZE);
      existing_data_p = new_ins_mvccid_pos_p;
      memmove (new_ins_mvccid_pos_p + OR_MVCCID_SIZE, existing_data_p,
           insert_context->recdes_p->length - OR_MVCC_INSERT_ID_OFFSET);
      insert_context->recdes_p->length += OR_MVCCID_SIZE;
    }

      /* Sets the MVCC INSID */
      OR_PUT_BIGINT (new_ins_mvccid_pos_p, &mvcc_id);

      return NO_ERROR;
    }

  /* read MVCC header from record */
  if (or_mvcc_get_header (insert_context->recdes_p, &mvcc_rec_header) != NO_ERROR)
    {
      return ER_FAILED;
    }

  if (insert_context->update_in_place != UPDATE_INPLACE_OLD_MVCCID)
    {
#if defined (SERVER_MODE)
      if (is_mvcc_class)
    {
      /* get MVCC id */
      mvcc_id = logtb_get_current_mvccid (thread_p);

      /* set MVCC INSID if necessary */
      if (!MVCC_IS_FLAG_SET (&mvcc_rec_header, OR_MVCC_FLAG_VALID_INSID))
        {
          MVCC_SET_FLAG (&mvcc_rec_header, OR_MVCC_FLAG_VALID_INSID);
          record_size += OR_MVCCID_SIZE;
        }
      MVCC_SET_INSID (&mvcc_rec_header, mvcc_id);
    }
      else
#endif /* SERVER_MODE */
    {
      int curr_header_size, new_header_size;

      /* strip MVCC information */
      curr_header_size = mvcc_header_size_lookup[mvcc_rec_header.mvcc_flag];
      MVCC_CLEAR_ALL_FLAG_BITS (&mvcc_rec_header);
      new_header_size = mvcc_header_size_lookup[mvcc_rec_header.mvcc_flag];

      /* compute new record size */
      record_size -= (curr_header_size - new_header_size);
    }
    }
  else if (MVCC_IS_HEADER_DELID_VALID (&mvcc_rec_header))
    {
      insert_context->is_redistribute_insert_with_delid = true;
    }

  MVCC_CLEAR_FLAG_BITS (&mvcc_rec_header, OR_MVCC_FLAG_VALID_PREV_VERSION);

  if (is_mvcc_class && heap_is_big_length (record_size))
    {
      /* for multipage records, set MVCC header size to maximum size */
      HEAP_MVCC_SET_HEADER_MAXIMUM_SIZE (&mvcc_rec_header);
    }

  /* write the header back to the record */
  if (or_mvcc_set_header (insert_context->recdes_p, &mvcc_rec_header) != NO_ERROR)
    {
      return ER_FAILED;
    }

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_update_adjust_recdes_header () - adjust record header for update
 *                                       operation
 *   thread_p(in): thread entry
 *   update_context(in/out): update context
 *   is_mvcc_class(in): specifies whether is MVCC class
 *   returns: error code or NO_ERROR
 *
 * NOTE: For MVCC operation, it will add an insert_id and prev version to the header. The prev_version_lsa will be
 *  filled at the end of the update, in heap_update_set_prev_version().
 *   For non-MVCC operations, it will clear all flags.
 *   The function will alter the provided record descriptor data area.
 */
static int
heap_update_adjust_recdes_header (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * update_context, bool is_mvcc_class)
{
  MVCC_REC_HEADER mvcc_rec_header;
  int record_size;
  int repid_and_flag_bits = 0, mvcc_flags = 0, update_mvcc_flags;
  char *start_p, *new_ins_mvccid_pos_p, *existing_data_p, *new_data_p;
  MVCCID mvcc_id;
  bool use_optimization = false;
  LOG_LSA null_lsa = LSA_INITIALIZER;
  bool is_mvcc_op = false;

  assert (update_context != NULL);
  assert (update_context->type == HEAP_OPERATION_UPDATE);
  assert (update_context->recdes_p != NULL);

  record_size = update_context->recdes_p->length;

  repid_and_flag_bits = OR_GET_MVCC_REPID_AND_FLAG (update_context->recdes_p->data);
  mvcc_flags = (repid_and_flag_bits >> OR_MVCC_FLAG_SHIFT_BITS) & OR_MVCC_FLAG_MASK;
  update_mvcc_flags = OR_MVCC_FLAG_VALID_INSID | OR_MVCC_FLAG_VALID_PREV_VERSION;

  is_mvcc_op = HEAP_UPDATE_IS_MVCC_OP (is_mvcc_class, update_context->update_in_place);
#if defined (SERVER_MODE)
  use_optimization = (is_mvcc_op && !heap_is_big_length (record_size + OR_MVCCID_SIZE + OR_MVCC_PREV_VERSION_LSA_SIZE));
#endif

  if (use_optimization)
    {
      /*
       * Most common case. Since is UPDATE_INPLACE_NONE, the header does not have DELID.
       * Optimize header adjustment.
       */
      assert (!(mvcc_flags & OR_MVCC_FLAG_VALID_DELID));
      mvcc_id = logtb_get_current_mvccid (thread_p);
      start_p = update_context->recdes_p->data;

      /* Skip bytes up to insid_offset */
      new_ins_mvccid_pos_p = start_p + OR_MVCC_INSERT_ID_OFFSET;

      /* Check whether we need to set flags and to reserve space. */
      if ((mvcc_flags & update_mvcc_flags) != update_mvcc_flags)
    {
      /* Need to set flags and reserve space for MVCCID and/or PREV LSA */
      existing_data_p = new_ins_mvccid_pos_p;

      /* Computes added bytes and new flags */
      if (mvcc_flags & OR_MVCC_FLAG_VALID_INSID)
        {
          existing_data_p += OR_MVCCID_SIZE;
        }

      if (mvcc_flags & OR_MVCC_FLAG_VALID_PREV_VERSION)
        {
          existing_data_p += OR_MVCC_PREV_VERSION_LSA_SIZE;
        }

      /* Sets the new flags, overwrite first four bytes. */
      repid_and_flag_bits |= (update_mvcc_flags << OR_MVCC_FLAG_SHIFT_BITS);
      OR_PUT_INT (start_p, repid_and_flag_bits);

      /* Move the record data before inserting INSID and LOG_LSA */
      new_data_p = new_ins_mvccid_pos_p + OR_MVCCID_SIZE + OR_MVCC_PREV_VERSION_LSA_SIZE;
      assert (existing_data_p < new_data_p);
      assert (update_context->recdes_p->area_size >= update_context->recdes_p->length
          + CAST_BUFLEN (new_data_p - existing_data_p));
      memmove (new_data_p, existing_data_p,
           update_context->recdes_p->length - CAST_BUFLEN (existing_data_p - start_p));
      update_context->recdes_p->length += (CAST_BUFLEN (new_data_p - existing_data_p));
    }

      /* Sets the MVCC INSID */
      OR_PUT_BIGINT (new_ins_mvccid_pos_p, &mvcc_id);

      /*
       * Adds NULL LSA after INSID. The prev_version_lsa will be filled at the end of the update,
       * in heap_update_set_prev_version().
       */
      memcpy (new_ins_mvccid_pos_p + OR_MVCCID_SIZE, &null_lsa, OR_MVCC_PREV_VERSION_LSA_SIZE);
      return NO_ERROR;
    }


  /* read MVCC header from record */
  if (or_mvcc_get_header (update_context->recdes_p, &mvcc_rec_header) != NO_ERROR)
    {
      return ER_FAILED;
    }

  if (update_context->update_in_place != UPDATE_INPLACE_OLD_MVCCID)
    {
#if defined (SERVER_MODE)
      if (is_mvcc_class)
    {
      /* get MVCC id */
      MVCCID mvcc_id = logtb_get_current_mvccid (thread_p);

      /* set MVCC INSID if necessary */
      if (!MVCC_IS_FLAG_SET (&mvcc_rec_header, OR_MVCC_FLAG_VALID_INSID))
        {
          MVCC_SET_FLAG (&mvcc_rec_header, OR_MVCC_FLAG_VALID_INSID);
          record_size += OR_MVCCID_SIZE;
        }
      MVCC_SET_INSID (&mvcc_rec_header, mvcc_id);
    }
      else
#endif /* SERVER_MODE */
    {
      int curr_header_size, new_header_size;

      /* strip MVCC information */
      curr_header_size = mvcc_header_size_lookup[mvcc_rec_header.mvcc_flag];
      MVCC_CLEAR_ALL_FLAG_BITS (&mvcc_rec_header);
      new_header_size = mvcc_header_size_lookup[mvcc_rec_header.mvcc_flag];

      /* compute new record size */
      record_size -= (curr_header_size - new_header_size);
    }
    }

#if defined (SERVER_MODE)
  if (is_mvcc_op)
    {
      if (!MVCC_IS_FLAG_SET (&mvcc_rec_header, OR_MVCC_FLAG_VALID_PREV_VERSION))
    {
      MVCC_SET_FLAG_BITS (&mvcc_rec_header, OR_MVCC_FLAG_VALID_PREV_VERSION);
      record_size += OR_MVCC_PREV_VERSION_LSA_SIZE;
    }

      /* The prev_version_lsa will be filled at the end of the update, in heap_update_set_prev_version() */
      LSA_SET_NULL (&mvcc_rec_header.prev_version_lsa);
    }
  else
#endif /* SERVER_MODE */
    {
      MVCC_CLEAR_FLAG_BITS (&mvcc_rec_header, OR_MVCC_FLAG_VALID_PREV_VERSION);
    }

  if (is_mvcc_class && heap_is_big_length (record_size))
    {
      /* for multipage records, set MVCC header size to maximum size */
      HEAP_MVCC_SET_HEADER_MAXIMUM_SIZE (&mvcc_rec_header);
    }

  /* write the header back to the record */
  if (or_mvcc_set_header (update_context->recdes_p, &mvcc_rec_header) != NO_ERROR)
    {
      return ER_FAILED;
    }

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_insert_handle_multipage_record () - handle a multipage object for insert
 *   thread_p(in): thread entry
 *   context(in): operation context
 *
 * NOTE: In case of multipage records, this function will perform the overflow
 *       insertion and provide a forwarding record descriptor in map_recdes.
 *       recdes_p will point to the map_recdes structure for insertion in home
 *       page.
 */
static int
heap_insert_handle_multipage_record (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_INSERT || context->type == HEAP_OPERATION_UPDATE);
  assert (context->recdes_p != NULL);

  /* check for big record */
  if (!heap_is_big_length (context->recdes_p->length))
    {
      return NO_ERROR;
    }

  /* insert overflow record */
  if (heap_ovf_insert (thread_p, &context->hfid, &context->ovf_oid, context->recdes_p) == NULL)
    {
      return ER_FAILED;
    }

  /* Add a map record to point to the record in overflow */
  /* NOTE: MVCC information is held in overflow record */
  heap_build_forwarding_recdes (&context->map_recdes, REC_BIGONE, &context->ovf_oid);

  /* use map_recdes for page insertion */
  context->recdes_p = &context->map_recdes;

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_get_insert_location_with_lock () - get a page (and possibly and slot)
 *                  for insert and lock the OID
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   home_hint_p(in): if not null, will try to find and lock a slot in hinted page
 *   returns: error code or NO_ERROR
 *
 * NOTE: For all operations, this function will find a suitable page, put it
 *       in context->home_page_watcher, find a suitable slot, lock it and
 *       put the exact insert location in context->res_oid.
 * NOTE: If a home hint is present, the function will search for a free and
 *       lockable slot ONLY in the hinted page. If no hint is present, it will
 *       find the page on it's own.
 */
static int
heap_get_insert_location_with_lock (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context,
                    PGBUF_WATCHER * home_hint_p)
{
  int slot_count, slot_id, lk_result;
  LOCK lock;
  int error_code = NO_ERROR;

  /* check input */
  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_INSERT);
  assert (context->recdes_p != NULL);

  if (home_hint_p == NULL)
    {
      /* find and fix page for insert */
      if (heap_stats_find_best_page (thread_p, &context->hfid, context->recdes_p->length,
                     (context->recdes_p->type != REC_NEWHOME), context->recdes_p->length,
                     context->scan_cache_p, context->home_page_watcher_p) == NULL)
    {
      ASSERT_ERROR_AND_SET (error_code);
      return error_code;
    }
    }
  else
    {
      assert (home_hint_p->pgptr != NULL);

      /* check page for space and use hinted page as insert page */
      if (spage_max_space_for_new_record (thread_p, home_hint_p->pgptr) < context->recdes_p->length)
    {
      return ER_SP_NOSPACE_IN_PAGE;
    }
      context->home_page_watcher_p = home_hint_p;
    }
  assert (context->home_page_watcher_p->pgptr != NULL);

  /* partially populate output OID */
  context->res_oid.volid = pgbuf_get_volume_id (context->home_page_watcher_p->pgptr);
  context->res_oid.pageid = pgbuf_get_page_id (context->home_page_watcher_p->pgptr);

  /* 
   * Find a slot that is lockable and lock it
   */
  /* determine lock type */
  if (OID_IS_ROOTOID (&context->class_oid))
    {
      /* class creation */
      lock = SCH_M_LOCK;
    }
  else
    {
      /* instance */
      lock = X_LOCK;
    }

  /* retrieve number of slots in page */
  slot_count = spage_number_of_slots (context->home_page_watcher_p->pgptr);

  /* find REC_DELETED_WILL_REUSE slot or add new slot */
  /* slot_id == slot_count means add new slot */
  for (slot_id = 0; slot_id <= slot_count; slot_id++)
    {
      slot_id = spage_find_free_slot (context->home_page_watcher_p->pgptr, NULL, slot_id);
      if (slot_id == SP_ERROR)
    {
      break;        /* this will not happen */
    }

      context->res_oid.slotid = slot_id;

      /* lock the object to be inserted conditionally */
      lk_result = lock_object (thread_p, &context->res_oid, &context->class_oid, lock, LK_COND_LOCK);
      if (lk_result == LK_GRANTED)
    {
      /* successfully locked! */
      return NO_ERROR;
    }
      else if (lk_result != LK_NOTGRANTED_DUE_TIMEOUT)
    {
#if !defined(NDEBUG)
      if (lk_result == LK_NOTGRANTED_DUE_ABORTED)
        {
          LOG_TDES *tdes = LOG_FIND_CURRENT_TDES (thread_p);
          assert (tdes->tran_abort_reason == TRAN_ABORT_DUE_ROLLBACK_ON_ESCALATION);
        }
      else
        {
          assert (false);   /* unknown locking error */
        }
#endif
      break;        /* go to error case */
    }
    }

  /* either lock error or no slot was found in page (which should not happen) */
  OID_SET_NULL (&context->res_oid);
  if (context->home_page_watcher_p != home_hint_p)
    {
      pgbuf_ordered_unfix (thread_p, context->home_page_watcher_p);
    }
  else
    {
      context->home_page_watcher_p = NULL;
    }
  assert (false);
  return ER_FAILED;
}


/*
 * heap_find_location_and_insert_rec_newhome  () - find location in a heap page
 *                  and then insert context->record
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   returns: error code or NO_ERROR
 *
 * NOTE: This function will find a suitable page, put it in
 *    context->home_page_watcher, insert context->recdes_p into that page
 *    and put recdes location into context->res_oid.
 *   Currently, this function is called only for REC_NEWHOME records, when
 *    lock acquisition is not required.
 *   The caller must log the inserted data.
 */
static int
heap_find_location_and_insert_rec_newhome (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  int sp_success;
  int error_code = NO_ERROR;

  /* check input */
  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_INSERT);
  assert (context->recdes_p != NULL);
  assert (context->recdes_p->type == REC_NEWHOME);

#if defined(CUBRID_DEBUG)
  if (heap_is_big_length (context->recdes_p->length))
    {
      er_log_debug (ARG_FILE_LINE,
            "heap_insert_internal: This function does not accept"
            " objects longer than %d. An object of %d was given\n", heap_Maxslotted_reclength, recdes->length);
      return ER_FAILED;
    }
#endif

  if (heap_stats_find_best_page (thread_p, &context->hfid, context->recdes_p->length, false, context->recdes_p->length,
                 context->scan_cache_p, context->home_page_watcher_p) == NULL)
    {
      ASSERT_ERROR_AND_SET (error_code);
      return error_code;
    }

#if !defined(NDEBUG)
  if (context->scan_cache_p != NULL)
    {
      OID heap_class_oid;

      assert (heap_get_class_oid_from_page (thread_p, context->home_page_watcher_p->pgptr, &heap_class_oid) ==
          NO_ERROR);

      assert (OID_EQ (&heap_class_oid, &context->scan_cache_p->node.class_oid));
    }
#endif

  assert (context->home_page_watcher_p->pgptr != NULL);
  (void) pgbuf_check_page_ptype (thread_p, context->home_page_watcher_p->pgptr, PAGE_HEAP);

  sp_success =
    spage_insert (thread_p, context->home_page_watcher_p->pgptr, context->recdes_p, &context->res_oid.slotid);
  if (sp_success == SP_SUCCESS)
    {
      context->res_oid.volid = pgbuf_get_volume_id (context->home_page_watcher_p->pgptr);
      context->res_oid.pageid = pgbuf_get_page_id (context->home_page_watcher_p->pgptr);

      return NO_ERROR;
    }
  else
    {
      assert (false);
      if (sp_success != SP_ERROR)
    {
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
    }
      OID_SET_NULL (&context->res_oid);
      pgbuf_ordered_unfix (thread_p, context->home_page_watcher_p);
      return ER_FAILED;
    }
}

/*
 * heap_insert_newhome () - will find an insert location for a REC_NEWHOME
 *                          record and will insert it there
 *   thread_p(in): thread entry
 *   parent_context(in): the context of the parent operation
 *   recdes_p(in): record descriptor of newhome record
 *   out_oid_p(in): pointer to an OID object to be populated with the result
 *                  OID of the insert
 *   newhome_pg_watcher(out): if not null, should keep the page watcher of newhome
                              - necessary to set prev version afterwards
 *   returns: error code or NO_ERROR
 *
 * NOTE: This function works ONLY in an MVCC operation. It will create a new
 *       context for the insert operation.
 */
static int
heap_insert_newhome (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * parent_context, RECDES * recdes_p,
             OID * out_oid_p, PGBUF_WATCHER * newhome_pg_watcher)
{
  HEAP_OPERATION_CONTEXT ins_context;
  int error_code = NO_ERROR;

  /* check input */
  assert (recdes_p != NULL);
  assert (parent_context != NULL);
  assert (parent_context->type == HEAP_OPERATION_DELETE || parent_context->type == HEAP_OPERATION_UPDATE);

  /* build insert context */
  heap_create_insert_context (&ins_context, &parent_context->hfid, &parent_context->class_oid, recdes_p, NULL);

  /* physical insertion */
  error_code = heap_find_location_and_insert_rec_newhome (thread_p, &ins_context);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }

  HEAP_PERF_TRACK_EXECUTE (thread_p, parent_context);

  /* log operation */

  /* This is a relocation of existing record, be it deleted or updated. Vacuum is not supposed to be notified since he
   * never check REC_NEWHOME type records. An MVCC type logging is not required here, a simple RVHF_INSERT will do. */
  heap_log_insert_physical (thread_p, ins_context.home_page_watcher_p->pgptr, &ins_context.hfid.vfid,
                &ins_context.res_oid, ins_context.recdes_p, false, false);

  HEAP_PERF_TRACK_LOGGING (thread_p, parent_context);

  /* advertise insert location */
  if (out_oid_p != NULL)
    {
      COPY_OID (out_oid_p, &ins_context.res_oid);
    }

  /* mark insert page as dirty */
  pgbuf_set_dirty (thread_p, ins_context.home_page_watcher_p->pgptr, DONT_FREE);

  if (newhome_pg_watcher != NULL)
    {
      /* keep the page watcher, necessary for heap_update_set_prev_version() */
      pgbuf_replace_watcher (thread_p, ins_context.home_page_watcher_p, newhome_pg_watcher);
    }

  /* unfix all pages of insert context */
  heap_unfix_watchers (thread_p, &ins_context);
  /* all ok */
  return NO_ERROR;
}

/*
 * heap_insert_physical () - physical insert into heap page
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   is_mvcc_op(in): MVCC or non-MVCC operation
 *
 * NOTE: This function should receive a fixed page and a location in res_oid,
 *       where the context->recdes_p will go in.
 */
static int
heap_insert_physical (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  /* check input */
  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_INSERT);
  assert (context->recdes_p != NULL);
  assert (context->home_page_watcher_p->pgptr != NULL);

  /* assume we have the exact location for insert as well as a fixed page */
  assert (context->res_oid.volid != NULL_VOLID);
  assert (context->res_oid.pageid != NULL_PAGEID);
  assert (context->res_oid.slotid != NULL_SLOTID);

#if defined(CUBRID_DEBUG)
  /* function should have received map record if input record was multipage */
  if (heap_is_big_length (context->recdes_p->length))
    {
      er_log_debug (ARG_FILE_LINE,
            "heap_insert_internal: This function does not accept"
            " objects longer than %d. An object of %d was given\n", heap_Maxslotted_reclength, recdes->length);
      return ER_FAILED;
    }

  /* check we're inserting in a page of desired class */
  if (!OID_ISNULL (&context->class_oid))
    {
      OID heap_class_oid;
      int rc;

      rc = heap_get_class_oid_from_page (thread_p, context->home_page_watcher_p->pgptr, &heap_class_oid);
      assert (rc == NO_ERROR);
      assert (OID_EQ (&heap_class_oid, &context->class_oid));
    }
#endif

  /* physical insertion */
  if (spage_insert_at (thread_p, context->home_page_watcher_p->pgptr, context->res_oid.slotid, context->recdes_p) !=
      SP_SUCCESS)
    {
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      OID_SET_NULL (&context->res_oid);
      return ER_FAILED;
    }

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_log_insert_physical () - add logging information for physical insertion
 *   thread_p(in): thread entry
 *   page_p(in): page where insert was performed
 *   vfid_p(in): virtual file id
 *   oid_p(in): newly inserted object id
 *   recdes_p(in): record descriptor of inserted record
 *   is_mvcc_op(in): specifies type of operation (MVCC/non-MVCC)
 *   is_redistribute_op(in): whether the insertion is due to partition
 *               redistribute operation and has a valid delid
 */
static void
heap_log_insert_physical (THREAD_ENTRY * thread_p, PAGE_PTR page_p, VFID * vfid_p, OID * oid_p, RECDES * recdes_p,
              bool is_mvcc_op, bool is_redistribute_op)
{
  LOG_DATA_ADDR log_addr;

  /* populate address field */
  log_addr.vfid = vfid_p;
  log_addr.offset = oid_p->slotid;
  log_addr.pgptr = page_p;

  if (is_mvcc_op)
    {
      if (is_redistribute_op)
    {
      /* this is actually a deleted record, inserted due to a PARTITION reorganize operation. Log this operation
       * separately */
      heap_mvcc_log_redistribute (thread_p, recdes_p, &log_addr);
    }
      else
    {
      /* MVCC logging */
      heap_mvcc_log_insert (thread_p, recdes_p, &log_addr);
    }
    }
  else
    {
      INT16 bytes_reserved;
      RECDES temp_recdes;

      if (recdes_p->type == REC_ASSIGN_ADDRESS)
    {
      /* special case for REC_ASSIGN */
      temp_recdes.type = recdes_p->type;
      temp_recdes.area_size = sizeof (bytes_reserved);
      temp_recdes.length = sizeof (bytes_reserved);
      bytes_reserved = (INT16) recdes_p->length;
      temp_recdes.data = (char *) &bytes_reserved;
      log_append_undoredo_recdes (thread_p, RVHF_INSERT, &log_addr, NULL, &temp_recdes);
    }
      else if (recdes_p->type == REC_NEWHOME)
    {
      /* replication for REC_NEWHOME is performed by following the link (OID) from REC_RELOCATION */
      log_append_undoredo_recdes (thread_p, RVHF_INSERT_NEWHOME, &log_addr, NULL, recdes_p);
    }
      else
    {
      log_append_undoredo_recdes (thread_p, RVHF_INSERT, &log_addr, NULL, recdes_p);
    }
    }
}

/*
 * heap_delete_adjust_header () - adjust MVCC record header for delete operation
 *
 *   header_p(in): MVCC record header
 *   mvcc_id(in): MVCC identifier
 *   need_mvcc_header_max_size(in): true, if need maximum size for MVCC header
 *
 * NOTE: Only applicable for MVCC operations.
 */
static void
heap_delete_adjust_header (MVCC_REC_HEADER * header_p, MVCCID mvcc_id, bool need_mvcc_header_max_size)
{
  assert (header_p != NULL);

  MVCC_SET_FLAG_BITS (header_p, OR_MVCC_FLAG_VALID_DELID);
  MVCC_SET_DELID (header_p, mvcc_id);

  if (need_mvcc_header_max_size)
    {
      /* set maximum MVCC header size */
      HEAP_MVCC_SET_HEADER_MAXIMUM_SIZE (header_p);
    }
}

/*
 * heap_get_delete_location () - find the desired object and fix the page
 *   thread_p(in): thread entry
 *   context(in): delete operation context
 *   return: error code or NO_ERROR
 */
static int
heap_get_record_location (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  VPID vpid;

  /* check input */
  assert (context != NULL);
  assert (!OID_ISNULL (&context->oid));
  assert (!HFID_IS_NULL (&context->hfid));

  /* get vpid from object */
  vpid.pageid = context->oid.pageid;
  vpid.volid = context->oid.volid;

  /* first try to retrieve cached fixed page from scancache */
  if (context->scan_cache_p != NULL && context->scan_cache_p->page_watcher.pgptr != NULL
      && context->scan_cache_p->cache_last_fix_page == true)
    {
      VPID *vpid_incache_p = pgbuf_get_vpid_ptr (context->scan_cache_p->page_watcher.pgptr);

      if (VPID_EQ (&vpid, vpid_incache_p))
    {
      /* we can get it from the scancache */
      pgbuf_replace_watcher (thread_p, &context->scan_cache_p->page_watcher, context->home_page_watcher_p);
    }
      else
    {
      /* last scancache fixed page is not desired page */
      pgbuf_ordered_unfix (thread_p, &context->scan_cache_p->page_watcher);
    }
      assert (context->scan_cache_p->page_watcher.pgptr == NULL);
    }

  /* if scancache page was not suitable, fix desired page */
  if (context->home_page_watcher_p->pgptr == NULL)
    {
      (void) heap_scan_pb_lock_and_fetch (thread_p, &vpid, OLD_PAGE, X_LOCK, context->scan_cache_p,
                      context->home_page_watcher_p);
      if (context->home_page_watcher_p->pgptr == NULL)
    {
      int rc;

      if (er_errid () == ER_PB_BAD_PAGEID)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, context->oid.volid,
              context->oid.pageid, context->oid.slotid);
        }

      /* something went wrong, return */
      ASSERT_ERROR_AND_SET (rc);
      return rc;
    }
    }

#if !defined(NDEBUG)
  if (context->scan_cache_p != NULL)
    {
      OID heap_class_oid;

      assert (heap_get_class_oid_from_page (thread_p, context->home_page_watcher_p->pgptr, &heap_class_oid) ==
          NO_ERROR);
      assert ((OID_EQ (&heap_class_oid, &context->scan_cache_p->node.class_oid))
          || (OID_ISNULL (&context->scan_cache_p->node.class_oid)
          && spage_get_record_type (context->home_page_watcher_p->pgptr,
                        context->oid.slotid) == REC_ASSIGN_ADDRESS));
    }
#endif

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_delete_bigone () - delete a REC_BIGONE record
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   is_mvcc_op(in): specifies type of operation (MVCC/non-MVCC)
 */
static int
heap_delete_bigone (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op)
{
  OID overflow_oid;
  int rc;

  /* check input */
  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_DELETE);
  assert (context->home_recdes.data != NULL);
  assert (context->home_page_watcher_p != NULL);
  assert (context->home_page_watcher_p->pgptr != NULL);
  assert (context->overflow_page_watcher_p != NULL);
  assert (context->overflow_page_watcher_p->pgptr == NULL);

  /* MVCC info is in overflow page, we only keep and OID in home */
  overflow_oid = *((OID *) context->home_recdes.data);

  /* reset overflow watcher rank */
  PGBUF_WATCHER_RESET_RANK (context->overflow_page_watcher_p, PGBUF_ORDERED_HEAP_OVERFLOW);

  if (is_mvcc_op)
    {
      MVCC_REC_HEADER overflow_header;
      VPID overflow_vpid;
      LOG_DATA_ADDR log_addr;
      MVCCID mvcc_id = logtb_get_current_mvccid (thread_p);

      /* fix overflow page */
      overflow_vpid.pageid = overflow_oid.pageid;
      overflow_vpid.volid = overflow_oid.volid;
      PGBUF_WATCHER_COPY_GROUP (context->overflow_page_watcher_p, context->home_page_watcher_p);
      rc = pgbuf_ordered_fix (thread_p, &overflow_vpid, OLD_PAGE, PGBUF_LATCH_WRITE, context->overflow_page_watcher_p);
      if (rc != NO_ERROR)
    {
      if (rc == ER_LK_PAGE_TIMEOUT && er_errid () == NO_ERROR)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PAGE_LATCH_ABORTED, 2, overflow_vpid.volid,
              overflow_vpid.pageid);
        }
      return rc;
    }

      /* check overflow page type */
      (void) pgbuf_check_page_ptype (thread_p, context->overflow_page_watcher_p->pgptr, PAGE_OVERFLOW);

      /* fetch header from overflow */
      if (heap_get_mvcc_rec_header_from_overflow (context->overflow_page_watcher_p->pgptr, &overflow_header, NULL) !=
      NO_ERROR)
    {
      return ER_FAILED;
    }
      assert (mvcc_header_size_lookup[overflow_header.mvcc_flag] == OR_MVCC_MAX_HEADER_SIZE);

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      /* log operation */
      log_addr.pgptr = context->overflow_page_watcher_p->pgptr;
      log_addr.vfid = &context->hfid.vfid;
      log_addr.offset = overflow_oid.slotid;
      heap_mvcc_log_delete (thread_p, &log_addr, RVHF_MVCC_DELETE_OVERFLOW);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* adjust header; we don't care to make header max size since it's already done */
      heap_delete_adjust_header (&overflow_header, mvcc_id, false);

      /* write header to overflow */
      rc = heap_set_mvcc_rec_header_on_overflow (context->overflow_page_watcher_p->pgptr, &overflow_header);
      if (rc != NO_ERROR)
    {
      return rc;
    }

      /* set page as dirty */
      pgbuf_set_dirty (thread_p, context->overflow_page_watcher_p->pgptr, DONT_FREE);

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      /* Home record is not changed, but page max MVCCID and vacuum status have to change. Also vacuum needs to be
       * vacuum with the location of home record (REC_RELOCATION). */
      log_addr.vfid = &context->hfid.vfid;
      log_addr.pgptr = context->home_page_watcher_p->pgptr;
      log_addr.offset = context->oid.slotid;
      heap_mvcc_log_home_no_change (thread_p, &log_addr);

      pgbuf_set_dirty (thread_p, context->home_page_watcher_p->pgptr, DONT_FREE);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      perfmon_inc_stat (thread_p, PSTAT_HEAP_BIG_MVCC_DELETES);
    }
  else
    {
      bool is_reusable = heap_is_reusable_oid (context->file_type);

      /* fix header page */
      rc = heap_fix_header_page (thread_p, context);
      if (rc != NO_ERROR)
    {
      return rc;
    }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      if (context->home_page_watcher_p->page_was_unfixed)
    {
      /* 
       * Need to get the record again, since record may have changed
       * by other transactions (INSID removed by VACUUM, page compact).
       * The object was already locked, so the record size may be the
       * same or smaller (INSID removed by VACUUM). 
       */
      int is_peeking = (context->home_recdes.area_size >= context->home_recdes.length) ? COPY : PEEK;
      if (spage_get_record (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                &context->home_recdes, is_peeking) != S_SUCCESS)
        {
          return ER_FAILED;
        }
    }

      /* log operation */
      heap_log_delete_physical (thread_p, context->home_page_watcher_p->pgptr, &context->hfid.vfid, &context->oid,
                &context->home_recdes, is_reusable, NULL);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* physical deletion of home record */
      rc = heap_delete_physical (thread_p, &context->hfid, context->home_page_watcher_p->pgptr, &context->oid);
      if (rc != NO_ERROR)
    {
      return rc;
    }

      /* physical deletion of overflow record */
      if (heap_ovf_delete (thread_p, &context->hfid, &overflow_oid, NULL) == NULL)
    {
      return ER_FAILED;
    }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      perfmon_inc_stat (thread_p, PSTAT_HEAP_BIG_DELETES);
    }

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_delete_relocation () - delete a REC_RELOCATION record
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   is_mvcc_op(in): specifies type of operation (MVCC/non-MVCC)
 *   returns: error code or NO_ERROR
 */
static int
heap_delete_relocation (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op)
{
  RECDES forward_recdes;
  OID forward_oid;
  int rc;

  /* check input */
  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_DELETE);
  assert (context->record_type == REC_RELOCATION);
  assert (context->home_page_watcher_p != NULL);
  assert (context->home_page_watcher_p->pgptr != NULL);
  assert (context->forward_page_watcher_p != NULL);

  /* get forward oid */
  forward_oid = *((OID *) context->home_recdes.data);

  /* fix forward page */
  if (heap_fix_forward_page (thread_p, context, &forward_oid) != NO_ERROR)
    {
      return ER_FAILED;
    }

  /* get forward record */
  if (spage_get_record (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid, &forward_recdes, PEEK) !=
      S_SUCCESS)
    {
      return ER_FAILED;
    }

  HEAP_PERF_TRACK_PREPARE (thread_p, context);

  if (is_mvcc_op)
    {
      RECDES new_forward_recdes, new_home_recdes;
      MVCC_REC_HEADER forward_rec_header;
      MVCCID mvcc_id = logtb_get_current_mvccid (thread_p);
      char buffer[IO_DEFAULT_PAGE_SIZE + OR_MVCC_MAX_HEADER_SIZE + MAX_ALIGNMENT];
      OID new_forward_oid;
      int adjusted_size;
      bool fits_in_home, fits_in_forward;
      bool update_old_home = false;
      bool update_old_forward = false;
      bool remove_old_forward = false;
      bool is_adjusted_size_big = false;
      int delid_offset, repid_and_flag_bits, mvcc_flags;
      char *build_recdes_data;
      bool use_optimization;

      repid_and_flag_bits = OR_GET_MVCC_REPID_AND_FLAG (forward_recdes.data);
      mvcc_flags = (repid_and_flag_bits >> OR_MVCC_FLAG_SHIFT_BITS) & OR_MVCC_FLAG_MASK;
      adjusted_size = forward_recdes.length;

      /*
       * Uses the optimization in most common cases, for now : if DELID not set and adjusted size is not big size.
       * Decide whether the deleted record has big size from beginning. After fixing header page, it may be possible
       * that the deleted record to not have big size. Since is a very rare case, don't care to optimize this case.
       */
      use_optimization = true;
      if (!(mvcc_flags & OR_MVCC_FLAG_VALID_DELID))
    {
      adjusted_size += OR_MVCCID_SIZE;
      is_adjusted_size_big = heap_is_big_length (adjusted_size);
      if (is_adjusted_size_big)
        {
          /* Rare case, do not optimize it now. */
          use_optimization = false;
        }
    }
      else
    {
      /* Rare case, do not optimize it now. */
      is_adjusted_size_big = false;
      use_optimization = false;
    }

#if !defined(NDEBUG)
      if (is_adjusted_size_big)
    {
      /* not exactly necessary, but we'll be able to compare sizes */
      adjusted_size = forward_recdes.length - mvcc_header_size_lookup[mvcc_flags] + OR_MVCC_MAX_HEADER_SIZE;
    }
#endif

      /* fix header if necessary */
      fits_in_home =
    spage_is_updatable (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid, adjusted_size);
      fits_in_forward =
    spage_is_updatable (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid, adjusted_size);
      if (is_adjusted_size_big || (!fits_in_forward && !fits_in_home))
    {
      /* fix header page */
      rc = heap_fix_header_page (thread_p, context);
      if (rc != NO_ERROR)
        {
          return ER_FAILED;
        }

      if (context->forward_page_watcher_p->page_was_unfixed)
        {
          /* re-peek forward record descriptor; forward page may have been unfixed by previous pgbuf_ordered_fix()
           * call */
          if (spage_get_record (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid,
                    &forward_recdes, PEEK) != S_SUCCESS)
        {
          return ER_FAILED;
        }

          /* Recomputes the header size, do not recomputes is_adjusted_size_big. */
          repid_and_flag_bits = OR_GET_MVCC_REPID_AND_FLAG (forward_recdes.data);
          if (mvcc_flags != ((repid_and_flag_bits >> OR_MVCC_FLAG_SHIFT_BITS) & OR_MVCC_FLAG_MASK))
        {
          /* Rare case - disable optimization, in case that the flags was modified meanwhile. */
          mvcc_flags = (repid_and_flag_bits >> OR_MVCC_FLAG_SHIFT_BITS) & OR_MVCC_FLAG_MASK;
          use_optimization = false;

#if !defined(NDEBUG)
          if (is_adjusted_size_big)
            {
              /* not exactly necessary, but we'll be able to compare sizes */
              adjusted_size = forward_recdes.length - mvcc_header_size_lookup[mvcc_flags]
            + OR_MVCC_MAX_HEADER_SIZE;
            }
#endif
        }
        }
    }

      /* Build the new record. */
      HEAP_SET_RECORD (&new_forward_recdes, IO_DEFAULT_PAGE_SIZE + OR_MVCC_MAX_HEADER_SIZE + MAX_ALIGNMENT, 0,
               REC_UNKNOWN, PTR_ALIGN (buffer, MAX_ALIGNMENT));
      if (use_optimization)
    {
      char *start_p;

      delid_offset = OR_MVCC_DELETE_ID_OFFSET (mvcc_flags);
      build_recdes_data = start_p = new_forward_recdes.data;

      /* Copy up to MVCC DELID first. */
      memcpy (build_recdes_data, forward_recdes.data, delid_offset);
      build_recdes_data += delid_offset;

      /* Sets MVCC DELID flag, overwrite first four bytes. */
      repid_and_flag_bits |= (OR_MVCC_FLAG_VALID_DELID << OR_MVCC_FLAG_SHIFT_BITS);
      OR_PUT_INT (start_p, repid_and_flag_bits);

      /* Sets the MVCC DELID. */
      OR_PUT_BIGINT (build_recdes_data, &mvcc_id);
      build_recdes_data += OR_MVCCID_SIZE;

      /* Copy remaining data. */
#if !defined(NDEBUG)
      if (mvcc_flags & OR_MVCC_FLAG_VALID_PREV_VERSION)
        {
          /* Check that we need to copy from offset of LOG LSA up to the end of the buffer. */
          assert (delid_offset == OR_MVCC_PREV_VERSION_LSA_OFFSET (mvcc_flags));
        }
      else
        {
          /* Check that we need to copy from end of MVCC header up to the end of the buffer. */
          assert (delid_offset == mvcc_header_size_lookup[mvcc_flags]);
        }
#endif

      memcpy (build_recdes_data, forward_recdes.data + delid_offset, forward_recdes.length - delid_offset);
      new_forward_recdes.length = adjusted_size;
    }
      else
    {
      int forward_rec_header_size;
      /*
       * Rare case - don't care to optimize it for now. Get the MVCC header, build adjusted record
       * header - slow operation.
       */
      if (or_mvcc_get_header (&forward_recdes, &forward_rec_header) != NO_ERROR)
        {
          return ER_FAILED;
        }
      assert (forward_rec_header.mvcc_flag == mvcc_flags);
      heap_delete_adjust_header (&forward_rec_header, mvcc_id, is_adjusted_size_big);
      or_mvcc_add_header (&new_forward_recdes, &forward_rec_header, OR_GET_BOUND_BIT_FLAG (forward_recdes.data),
                  OR_GET_OFFSET_SIZE (forward_recdes.data));

      forward_rec_header_size = mvcc_header_size_lookup[mvcc_flags];
      memcpy (new_forward_recdes.data + new_forward_recdes.length, forward_recdes.data + forward_rec_header_size,
          forward_recdes.length - forward_rec_header_size);
      new_forward_recdes.length += forward_recdes.length - forward_rec_header_size;
      assert (new_forward_recdes.length == adjusted_size);
    }

      /* determine what operations on home/forward pages are necessary and execute extra operations for each case */
      if (is_adjusted_size_big)
    {
      /* insert new overflow record */
      if (heap_ovf_insert (thread_p, &context->hfid, &new_forward_oid, &new_forward_recdes) == NULL)
        {
          return ER_FAILED;
        }

      /* home record descriptor will be an overflow OID and will be placed in original home page */
      heap_build_forwarding_recdes (&new_home_recdes, REC_BIGONE, &new_forward_oid);

      /* remove old forward record */
      remove_old_forward = true;
      update_old_home = true;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_REL_TO_BIG_DELETES);
    }
      else if (fits_in_home)
    {
      /* updated forward record fits in home page */
      new_home_recdes = new_forward_recdes;
      new_home_recdes.type = REC_HOME;

      /* clear forward rebuild_record (just to be safe) */
      new_forward_recdes.area_size = 0;
      new_forward_recdes.length = 0;
      new_forward_recdes.type = REC_UNKNOWN;
      new_forward_recdes.data = NULL;

      /* remove old forward record */
      remove_old_forward = true;
      update_old_home = true;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_REL_TO_HOME_DELETES);
    }
      else if (fits_in_forward)
    {
      /* updated forward record fits in old forward page */
      new_forward_recdes.type = REC_NEWHOME;

      /* home record will not be touched */
      update_old_forward = true;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_REL_MVCC_DELETES);
    }
      else
    {
      /* doesn't fit in either home or forward page */
      /* insert a new forward record */
      new_forward_recdes.type = REC_NEWHOME;
      rc = heap_insert_newhome (thread_p, context, &new_forward_recdes, &new_forward_oid, NULL);
      if (rc != NO_ERROR)
        {
          return rc;
        }

      /* new home record will be a REC_RELOCATION and will be placed in the original home page */
      heap_build_forwarding_recdes (&new_home_recdes, REC_RELOCATION, &new_forward_oid);

      /* remove old forward record */
      remove_old_forward = true;
      update_old_home = true;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_REL_TO_REL_DELETES);
    }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      /* 
       * Update old home record (if necessary)
       */
      if (update_old_home)
    {
      LOG_DATA_ADDR home_addr;

      if (context->home_page_watcher_p->page_was_unfixed)
        {
          /* 
           * Need to get the record again, since record may have changed
           * by other transactions (INSID removed by VACUUM, page compact).
           * The object was already locked, so the record size may be the
           * same or smaller (INSID removed by VACUUM). 
           */
          int is_peeking = (context->home_recdes.area_size >= context->home_recdes.length) ? COPY : PEEK;
          if (spage_get_record (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                    &context->home_recdes, is_peeking) != S_SUCCESS)
        {
          return ER_FAILED;
        }
        }

      /* log operation */
      home_addr.vfid = &context->hfid.vfid;
      home_addr.pgptr = context->home_page_watcher_p->pgptr;
      home_addr.offset = context->oid.slotid;

      heap_mvcc_log_home_change_on_delete (thread_p, &context->home_recdes, &new_home_recdes, &home_addr);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* update home record */
      rc = heap_update_physical (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                     &new_home_recdes);
      if (rc != NO_ERROR)
        {
          return rc;
        }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
    }
      else
    {
      /* Home record is not changed, but page max MVCCID and vacuum status have to change. Also vacuum needs to be
       * vacuum with the location of home record (REC_BIGONE). */
      LOG_DATA_ADDR home_addr;

      /* log operation */
      home_addr.vfid = &context->hfid.vfid;
      home_addr.pgptr = context->home_page_watcher_p->pgptr;
      home_addr.offset = context->oid.slotid;
      heap_mvcc_log_home_no_change (thread_p, &home_addr);
      pgbuf_set_dirty (thread_p, context->home_page_watcher_p->pgptr, DONT_FREE);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);
    }

      /* 
       * Update old forward record (if necessary)
       */
      if (update_old_forward)
    {
      LOG_DATA_ADDR forward_addr;

      /* log operation */
      forward_addr.vfid = &context->hfid.vfid;
      forward_addr.pgptr = context->forward_page_watcher_p->pgptr;
      forward_addr.offset = forward_oid.slotid;
      heap_mvcc_log_delete (thread_p, &forward_addr, RVHF_MVCC_DELETE_REC_NEWHOME);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* physical update of forward record */
      rc =
        heap_update_physical (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid,
                  &new_forward_recdes);
      if (rc != NO_ERROR)
        {
          return rc;
        }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
    }

      /* 
       * Delete old forward record (if necessary)
       */
      if (remove_old_forward)
    {
      LOG_DATA_ADDR forward_addr;

      /* re-peek forward record descriptor; forward page may have been unfixed by previous pgbuf_ordered_fix() call 
       */
      if (context->forward_page_watcher_p->page_was_unfixed)
        {
          if (spage_get_record (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid,
                    &forward_recdes, PEEK) != S_SUCCESS)
        {
          return ER_FAILED;
        }
        }

      /* operation logging */
      forward_addr.vfid = &context->hfid.vfid;
      forward_addr.pgptr = context->forward_page_watcher_p->pgptr;
      forward_addr.offset = forward_oid.slotid;

      log_append_undoredo_recdes (thread_p, RVHF_DELETE, &forward_addr, &forward_recdes, NULL);
      if (heap_is_reusable_oid (context->file_type))
        {
          log_append_postpone (thread_p, RVHF_MARK_REUSABLE_SLOT, &forward_addr, 0, NULL);
        }

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* physical removal of forward record */
      rc = heap_delete_physical (thread_p, &context->hfid, context->forward_page_watcher_p->pgptr, &forward_oid);
      if (rc != NO_ERROR)
        {
          return rc;
        }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
    }
    }
  else
    {
      bool is_reusable = heap_is_reusable_oid (context->file_type);

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      if (context->home_page_watcher_p->page_was_unfixed)
    {
      /* 
       * Need to get the record again, since record may have changed
       * by other transactions (INSID removed by VACUUM, page compact).
       * The object was already locked, so the record size may be the
       * same or smaller (INSID removed by VACUUM). 
       */
      int is_peeking = (context->home_recdes.area_size >= context->home_recdes.length) ? COPY : PEEK;
      if (spage_get_record (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                &context->home_recdes, is_peeking) != S_SUCCESS)
        {
          return ER_FAILED;
        }
    }
      /* 
       * Delete home record
       */

      heap_log_delete_physical (thread_p, context->home_page_watcher_p->pgptr, &context->hfid.vfid, &context->oid,
                &context->home_recdes, is_reusable, NULL);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* physical deletion of home record */
      rc = heap_delete_physical (thread_p, &context->hfid, context->home_page_watcher_p->pgptr, &context->oid);
      if (rc != NO_ERROR)
    {
      return rc;
    }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      if (context->forward_page_watcher_p->page_was_unfixed)
    {
      /* re-peek forward record descriptor; forward page may have been unfixed by previous pgbuf_ordered_fix() call 
       */
      if (spage_get_record (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid,
                &forward_recdes, PEEK) != S_SUCCESS)
        {
          return ER_FAILED;
        }
    }
      /* 
       * Delete forward record
       */
      /* 
       * It should be safe to mark the new home slot as reusable regardless
       * of the heap type (reusable OID or not) as the relocated record
       * should not be referenced anywhere in the database.
       */
      heap_log_delete_physical (thread_p, context->forward_page_watcher_p->pgptr, &context->hfid.vfid, &forward_oid,
                &forward_recdes, true, NULL);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* physical deletion of forward record */
      rc = heap_delete_physical (thread_p, &context->hfid, context->forward_page_watcher_p->pgptr, &forward_oid);
      if (rc != NO_ERROR)
    {
      return rc;
    }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      perfmon_inc_stat (thread_p, PSTAT_HEAP_REL_DELETES);
    }

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_delete_home () - delete a REC_HOME (or REC_ASSIGN_ADDRESS) record
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   is_mvcc_op(in): specifies type of operation (MVCC/non-MVCC)
 *   returns: error code or NO_ERROR
 */
static int
heap_delete_home (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op)
{
  int error_code = NO_ERROR;

  /* check input */
  assert (context != NULL);
  assert (context->record_type == REC_HOME || context->record_type == REC_ASSIGN_ADDRESS);
  assert (context->type == HEAP_OPERATION_DELETE);
  assert (context->home_page_watcher_p != NULL);
  assert (context->home_page_watcher_p->pgptr != NULL);

  if (context->home_page_watcher_p->page_was_unfixed)
    {
      /* 
       * Need to get the record again, since record may have changed
       * by other transactions (INSID removed by VACUUM, page compact).
       * The object was already locked, so the record size may be the
       * same or smaller (INSID removed by VACUUM). 
       */
      int is_peeking = (context->home_recdes.area_size >= context->home_recdes.length) ? COPY : PEEK;
      if (spage_get_record (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                &context->home_recdes, is_peeking) != S_SUCCESS)
    {
      assert (false);
      return ER_FAILED;
    }
    }

  /* operation */
  if (is_mvcc_op)
    {
      MVCC_REC_HEADER record_header;
      RECDES built_recdes;
      RECDES forwarding_recdes;
      RECDES *home_page_updated_recdes;
      OID forward_oid;
      MVCCID mvcc_id = logtb_get_current_mvccid (thread_p);
      char data_buffer[IO_DEFAULT_PAGE_SIZE + OR_MVCC_MAX_HEADER_SIZE + MAX_ALIGNMENT];
      int adjusted_size;
      bool is_adjusted_size_big = false;
      int delid_offset, repid_and_flag_bits, mvcc_flags;
      char *build_recdes_data;
      bool use_optimization;

      /* Build the new record descriptor. */
      repid_and_flag_bits = OR_GET_MVCC_REPID_AND_FLAG (context->home_recdes.data);
      mvcc_flags = (repid_and_flag_bits >> OR_MVCC_FLAG_SHIFT_BITS) & OR_MVCC_FLAG_MASK;
      adjusted_size = context->home_recdes.length;

      /* Uses the optimization in most common cases, for now : if DELID not set and adjusted size is not big size. */
      use_optimization = true;
      if (!(mvcc_flags & OR_MVCC_FLAG_VALID_DELID))
    {
      adjusted_size += OR_MVCCID_SIZE;
      is_adjusted_size_big = heap_is_big_length (adjusted_size);
      if (is_adjusted_size_big)
        {
          /* Rare case, do not optimize it now. */
          use_optimization = false;
        }
    }
      else
    {
      /* Rare case, do not optimize it now. */
      is_adjusted_size_big = false;
      use_optimization = false;
    }

#if !defined(NDEBUG)
      if (is_adjusted_size_big)
    {
      /* not exactly necessary, but we'll be able to compare sizes */
      adjusted_size = context->home_recdes.length - mvcc_header_size_lookup[mvcc_flags] + OR_MVCC_MAX_HEADER_SIZE;
    }
#endif

      /* Build the new record. */
      HEAP_SET_RECORD (&built_recdes, IO_DEFAULT_PAGE_SIZE + OR_MVCC_MAX_HEADER_SIZE, 0, REC_UNKNOWN,
               PTR_ALIGN (data_buffer, MAX_ALIGNMENT));
      if (use_optimization)
    {
      char *start_p;

      delid_offset = OR_MVCC_DELETE_ID_OFFSET (mvcc_flags);

      build_recdes_data = start_p = built_recdes.data;

      /* Copy up to MVCC DELID first. */
      memcpy (build_recdes_data, context->home_recdes.data, delid_offset);
      build_recdes_data += delid_offset;

      /* Sets MVCC DELID flag, overwrite first four bytes. */
      repid_and_flag_bits |= (OR_MVCC_FLAG_VALID_DELID << OR_MVCC_FLAG_SHIFT_BITS);
      OR_PUT_INT (start_p, repid_and_flag_bits);

      /* Sets the MVCC DELID. */
      OR_PUT_BIGINT (build_recdes_data, &mvcc_id);
      build_recdes_data += OR_MVCC_DELETE_ID_SIZE;

      /* Copy remaining data. */
#if !defined(NDEBUG)
      if (mvcc_flags & OR_MVCC_FLAG_VALID_PREV_VERSION)
        {
          /* Check that we need to copy from offset of LOG LSA up to the end of the buffer. */
          assert (delid_offset == OR_MVCC_PREV_VERSION_LSA_OFFSET (mvcc_flags));
        }
      else
        {
          /* Check that we need to copy from end of MVCC header up to the end of the buffer. */
          assert (delid_offset == mvcc_header_size_lookup[mvcc_flags]);
        }
#endif

      memcpy (build_recdes_data, context->home_recdes.data + delid_offset,
          context->home_recdes.length - delid_offset);
      built_recdes.length = adjusted_size;
    }
      else
    {
      int header_size;
      /*
       * Rare case - don't care to optimize it for now. Get the MVCC header, build adjusted record
       * header - slow operation.
       */
      error_code = or_mvcc_get_header (&context->home_recdes, &record_header);
      if (error_code != NO_ERROR)
        {
          ASSERT_ERROR ();
          return error_code;
        }
      assert (record_header.mvcc_flag == mvcc_flags);

      heap_delete_adjust_header (&record_header, mvcc_id, is_adjusted_size_big);
      or_mvcc_add_header (&built_recdes, &record_header, OR_GET_BOUND_BIT_FLAG (context->home_recdes.data),
                  OR_GET_OFFSET_SIZE (context->home_recdes.data));
      header_size = mvcc_header_size_lookup[mvcc_flags];
      memcpy (built_recdes.data + built_recdes.length, context->home_recdes.data + header_size,
          context->home_recdes.length - header_size);
      built_recdes.length += (context->home_recdes.length - header_size);
      assert (built_recdes.length == adjusted_size);
    }

      /* determine type */
      if (is_adjusted_size_big)
    {
      built_recdes.type = REC_BIGONE;
    }
      else if (!spage_is_updatable (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                    built_recdes.length))
    {
      built_recdes.type = REC_NEWHOME;
    }
      else
    {
      built_recdes.type = REC_HOME;
    }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      /* check whether relocation is necessary */
      if (built_recdes.type == REC_BIGONE || built_recdes.type == REC_NEWHOME)
    {
      /* 
       * Relocation necessary
       */
      LOG_DATA_ADDR rec_address;

      /* insertion of built record */
      if (built_recdes.type == REC_BIGONE)
        {
          /* new record is overflow record - REC_BIGONE case */
          forwarding_recdes.type = REC_BIGONE;
          if (heap_ovf_insert (thread_p, &context->hfid, &forward_oid, &built_recdes) == NULL)
        {
          ASSERT_ERROR_AND_SET (error_code);
          return error_code;
        }

          perfmon_inc_stat (thread_p, PSTAT_HEAP_HOME_TO_BIG_DELETES);
        }
      else
        {
          /* new record is relocated - REC_NEWHOME case */
          forwarding_recdes.type = REC_RELOCATION;

          /* insert NEWHOME record */
          error_code = heap_insert_newhome (thread_p, context, &built_recdes, &forward_oid, NULL);
          if (error_code != NO_ERROR)
        {
          ASSERT_ERROR ();
          return error_code;
        }

          perfmon_inc_stat (thread_p, PSTAT_HEAP_HOME_TO_REL_DELETES);
        }

      /* build forwarding rebuild_record */
      heap_build_forwarding_recdes (&forwarding_recdes, forwarding_recdes.type, &forward_oid);

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      if (context->home_page_watcher_p->page_was_unfixed)
        {
          /* 
           * Need to get the record again, since record may have changed
           * by other transactions (INSID removed by VACUUM, page compact).
           * The object was already locked, so the record size may be the
           * same or smaller (INSID removed by VACUUM). 
           */
          int is_peeking = (context->home_recdes.area_size >= context->home_recdes.length) ? COPY : PEEK;
          if (spage_get_record (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                    &context->home_recdes, is_peeking) != S_SUCCESS)
        {
          assert (false);
          return ER_FAILED;
        }
        }

      /* log relocation */
      rec_address.pgptr = context->home_page_watcher_p->pgptr;
      rec_address.vfid = &context->hfid.vfid;
      rec_address.offset = context->oid.slotid;
      heap_mvcc_log_home_change_on_delete (thread_p, &context->home_recdes, &forwarding_recdes, &rec_address);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* we'll update the home page with the forwarding record */
      home_page_updated_recdes = &forwarding_recdes;
    }
      else
    {
      LOG_DATA_ADDR rec_address;

      /* 
       * No relocation, can be updated in place
       */

      rec_address.pgptr = context->home_page_watcher_p->pgptr;
      rec_address.vfid = &context->hfid.vfid;
      rec_address.offset = context->oid.slotid;
      heap_mvcc_log_delete (thread_p, &rec_address, RVHF_MVCC_DELETE_REC_HOME);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* we'll update the home page with the built record, since it fits in home page */
      home_page_updated_recdes = &built_recdes;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_HOME_MVCC_DELETES);
    }

      /* update home page and check operation result */
      error_code =
    heap_update_physical (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                  home_page_updated_recdes);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
    }
  else
    {
      bool is_reusable = heap_is_reusable_oid (context->file_type);

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      /* log operation */
      heap_log_delete_physical (thread_p, context->home_page_watcher_p->pgptr, &context->hfid.vfid, &context->oid,
                &context->home_recdes, is_reusable, NULL);

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* physical deletion */
      error_code = heap_delete_physical (thread_p, &context->hfid, context->home_page_watcher_p->pgptr, &context->oid);

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      perfmon_inc_stat (thread_p, PSTAT_HEAP_HOME_DELETES);

      assert (error_code == NO_ERROR || er_errid () != NO_ERROR);
      return error_code;
    }

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_delete_physical () - physical deletion of a record
 *   thread_p(in): thread entry
 *   hfid_p(in): heap file identifier where record is located
 *   page_p(in): page where record is stored
 *   oid_p(in): object identifier of record
 */
static int
heap_delete_physical (THREAD_ENTRY * thread_p, HFID * hfid_p, PAGE_PTR page_p, OID * oid_p)
{
  int free_space;

  /* check input */
  assert (hfid_p != NULL);
  assert (page_p != NULL);
  assert (oid_p != NULL);
  assert (oid_p->slotid != NULL_SLOTID);

  /* save old freespace */
  free_space = spage_get_free_space_without_saving (thread_p, page_p, NULL);

  /* physical deletion */
  if (spage_delete (thread_p, page_p, oid_p->slotid) == NULL_SLOTID)
    {
      return ER_FAILED;
    }

  /* update statistics */
  heap_stats_update (thread_p, page_p, hfid_p, free_space);

  /* mark page as dirty */
  pgbuf_set_dirty (thread_p, page_p, DONT_FREE);

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_log_delete_physical () - log physical deletion
 *   thread_p(in): thread entry
 *   page_p(in): page pointer
 *   vfid_p(in): virtual file identifier
 *   oid_p(in): object identifier of deleted record
 *   recdes_p(in): record descriptor of deleted record
 *   mark_reusable(in): if true, will mark the slot as reusable
 *   undo_lsa(out): lsa to the undo record; needed to set previous version lsa of record at update
 */
static void
heap_log_delete_physical (THREAD_ENTRY * thread_p, PAGE_PTR page_p, VFID * vfid_p, OID * oid_p, RECDES * recdes_p,
              bool mark_reusable, LOG_LSA * undo_lsa)
{
  LOG_DATA_ADDR log_addr;

  /* check input */
  assert (page_p != NULL);
  assert (vfid_p != NULL);
  assert (oid_p != NULL);
  assert (recdes_p != NULL);

  /* populate address */
  log_addr.offset = oid_p->slotid;
  log_addr.pgptr = page_p;
  log_addr.vfid = vfid_p;

  if (recdes_p->type == REC_ASSIGN_ADDRESS)
    {
      /* special case for REC_ASSIGN */
      RECDES temp_recdes;
      INT16 bytes_reserved;

      temp_recdes.type = recdes_p->type;
      temp_recdes.area_size = sizeof (bytes_reserved);
      temp_recdes.length = sizeof (bytes_reserved);
      bytes_reserved = (INT16) recdes_p->length;
      temp_recdes.data = (char *) &bytes_reserved;

      log_append_undoredo_recdes (thread_p, RVHF_DELETE, &log_addr, &temp_recdes, NULL);
    }
  else
    {
      /* log record descriptor */
      log_append_undoredo_recdes (thread_p, RVHF_DELETE, &log_addr, recdes_p, NULL);
    }

  if (undo_lsa)
    {
      /* get, set undo lsa before log_append_postpone() will make it inaccessible */
      LSA_COPY (undo_lsa, logtb_find_current_tran_lsa (thread_p));
    }

  /* log postponed operation */
  if (mark_reusable)
    {
      log_append_postpone (thread_p, RVHF_MARK_REUSABLE_SLOT, &log_addr, 0, NULL);
    }
}

/*
 * heap_update_bigone () - update a REC_BIGONE record
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   is_mvcc_op(in): type of operation (MVCC/non-MVCC)
 */
static int
heap_update_bigone (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op)
{
  int error_code = NO_ERROR;
  bool is_old_home_updated;
  RECDES new_home_recdes;

  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_UPDATE);
  assert (context->recdes_p != NULL);
  assert (context->home_page_watcher_p != NULL);
  assert (context->home_page_watcher_p->pgptr != NULL);
  assert (context->overflow_page_watcher_p != NULL);

  /* read OID of overflow record */
  context->ovf_oid = *((OID *) context->home_recdes.data);

  /* fix header page */
  error_code = heap_fix_header_page (thread_p, context);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

  HEAP_PERF_TRACK_PREPARE (thread_p, context);

  if (is_mvcc_op)
    {
      /* log old overflow record and set prev version lsa */

      /* This undo log record have two roles: 1) to keep the old record version; 2) to reach the record at undo
       * in order to check if it should have its insert id and prev version vacuumed; */
      RECDES ovf_recdes = RECDES_INITIALIZER;
      VPID ovf_vpid;
      PAGE_PTR first_pgptr;

      if (heap_get_bigone_content (thread_p, context->scan_cache_p, COPY, &context->ovf_oid, &ovf_recdes) != S_SUCCESS)
    {
      error_code = ER_FAILED;
      goto exit;
    }

      VPID_GET_FROM_OID (&ovf_vpid, &context->ovf_oid);
      first_pgptr = pgbuf_fix (thread_p, &ovf_vpid, OLD_PAGE, PGBUF_LATCH_WRITE, PGBUF_UNCONDITIONAL_LATCH);
      if (first_pgptr == NULL)
    {
      error_code = ER_FAILED;
      goto exit;
    }

      /* actual logging */
      log_append_undo_recdes2 (thread_p, RVHF_MVCC_UPDATE_OVERFLOW, NULL, first_pgptr, -1, &ovf_recdes);
      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      pgbuf_set_dirty (thread_p, first_pgptr, FREE);

      /* set prev version lsa */
      or_mvcc_set_log_lsa_to_record (context->recdes_p, logtb_find_current_tran_lsa (thread_p));
    }

  /* Proceed with the update. the new record is prepared and for mvcc it should have the prev version lsa set */
  if (heap_is_big_length (context->recdes_p->length))
    {
      /* overflow -> overflow update */
      is_old_home_updated = false;

      if (heap_ovf_update (thread_p, &context->hfid, &context->ovf_oid, context->recdes_p) == NULL)
    {
      ASSERT_ERROR_AND_SET (error_code);
      goto exit;
    }
      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      if (is_mvcc_op)
    {
      /* log home no change; vacuum needs it to reach the updated overflow record */
      LOG_DATA_ADDR log_addr;

      LOG_SET_DATA_ADDR (&log_addr, context->home_page_watcher_p->pgptr, &context->hfid.vfid, context->oid.slotid);

      heap_mvcc_log_home_no_change (thread_p, &log_addr);

      /* dirty home page because of logging */
      pgbuf_set_dirty (thread_p, context->home_page_watcher_p->pgptr, DONT_FREE);
      HEAP_PERF_TRACK_LOGGING (thread_p, context);
    }
    }
  else if (spage_update (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid, context->recdes_p) ==
       SP_SUCCESS)
    {
      /* overflow -> rec home update (new record fits in home page) */
      is_old_home_updated = true;

      /* update it's type in the page */
      context->record_type = context->recdes_p->type = REC_HOME;
      spage_update_record_type (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                context->recdes_p->type);

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);

      new_home_recdes = *context->recdes_p;

      /* dirty home page */
      pgbuf_set_dirty (thread_p, context->home_page_watcher_p->pgptr, DONT_FREE);
    }
  else
    {
      /* overflow -> rec relocation update (home record will point to the new_home record) */
      OID newhome_oid;

      /* insert new home */
      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
      context->recdes_p->type = REC_NEWHOME;
      error_code = heap_insert_newhome (thread_p, context, context->recdes_p, &newhome_oid, NULL);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

      /* prepare record descriptor */
      heap_build_forwarding_recdes (&new_home_recdes, REC_RELOCATION, &newhome_oid);

      /* update home */
      error_code = heap_update_physical (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                     &new_home_recdes);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }
      is_old_home_updated = true;

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
    }

  if (is_old_home_updated)
    {
      /* log home update operation and remove old overflow record */
      heap_log_update_physical (thread_p, context->home_page_watcher_p->pgptr, &context->hfid.vfid,
                &context->oid, &context->home_recdes, &new_home_recdes,
                (is_mvcc_op ? RVHF_UPDATE_NOTIFY_VACUUM : RVHF_UPDATE));
      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* the old overflow record is no longer needed, it was linked only by old home */
      if (heap_ovf_delete (thread_p, &context->hfid, &context->ovf_oid, NULL) == NULL)
    {
      ASSERT_ERROR_AND_SET (error_code);
      goto exit;
    }
      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
    }

  /* location did not change */
  COPY_OID (&context->res_oid, &context->oid);

  perfmon_inc_stat (thread_p, PSTAT_HEAP_BIG_UPDATES);

  /* Fall through to exit. */

exit:
  return error_code;
}

/*
 * heap_update_relocation () - update a REC_RELOCATION/REC_NEWHOME combo
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   is_mvcc_op(in): type of operation (MVCC/non-MVCC)
 */
static int
heap_update_relocation (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op)
{
  RECDES forward_recdes;
  char forward_recdes_buffer[IO_MAX_PAGE_SIZE + MAX_ALIGNMENT];
  OID forward_oid;
  int rc;
  RECDES new_home_recdes;
  OID new_forward_oid;
  bool fits_in_home, fits_in_forward;
  bool update_old_home = false;
  bool update_old_forward = false;
  bool remove_old_forward = false;
  LOG_LSA prev_version_lsa = LSA_INITIALIZER;
  PGBUF_WATCHER newhome_pg_watcher; /* fwd pg watcher required for heap_update_set_prev_version() */
  PGBUF_WATCHER *newhome_pg_watcher_p = NULL;

  assert (context != NULL);
  assert (context->recdes_p != NULL);
  assert (context->type == HEAP_OPERATION_UPDATE);
  assert (context->home_page_watcher_p != NULL);
  assert (context->home_page_watcher_p->pgptr != NULL);
  assert (context->forward_page_watcher_p != NULL);

  /* get forward oid */
  forward_oid = *((OID *) context->home_recdes.data);

  /* fix forward page */
  rc = heap_fix_forward_page (thread_p, context, &forward_oid);
  if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

  /* fix header if necessary */
  fits_in_home =
    spage_is_updatable (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid, context->recdes_p->length);
  fits_in_forward =
    spage_is_updatable (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid,
            context->recdes_p->length);
  if (heap_is_big_length (context->recdes_p->length) || (!fits_in_forward && !fits_in_home))
    {
      /* fix header page */
      rc = heap_fix_header_page (thread_p, context);
      if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }
    }

  /* get forward record */
  forward_recdes.area_size = DB_PAGESIZE;
  forward_recdes.data = PTR_ALIGN (forward_recdes_buffer, MAX_ALIGNMENT);
  if (spage_get_record (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid, &forward_recdes, COPY) !=
      S_SUCCESS)
    {
      assert (false);
      ASSERT_ERROR_AND_SET (rc);
      goto exit;
    }

  HEAP_PERF_TRACK_PREPARE (thread_p, context);

  /* determine what operations on home/forward pages are necessary and execute extra operations for each case */
  if (heap_is_big_length (context->recdes_p->length))
    {
      /* insert new overflow record */
      if (heap_ovf_insert (thread_p, &context->hfid, &new_forward_oid, context->recdes_p) == NULL)
    {
      ASSERT_ERROR_AND_SET (rc);
      goto exit;
    }

      /* home record descriptor will be an overflow OID and will be placed in original home page */
      heap_build_forwarding_recdes (&new_home_recdes, REC_BIGONE, &new_forward_oid);

      /* remove old forward record */
      remove_old_forward = true;
      update_old_home = true;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_REL_TO_BIG_UPDATES);
    }
  else if (!fits_in_forward && !fits_in_home)
    {
      /* insert a new forward record */

      if (is_mvcc_op)
    {
      /* necessary later to set prev version, which is required only for mvcc objects */
      newhome_pg_watcher_p = &newhome_pg_watcher;
      PGBUF_INIT_WATCHER (newhome_pg_watcher_p, PGBUF_ORDERED_HEAP_NORMAL, PGBUF_ORDERED_NULL_HFID);
    }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
      context->recdes_p->type = REC_NEWHOME;
      rc = heap_insert_newhome (thread_p, context, context->recdes_p, &new_forward_oid, newhome_pg_watcher_p);
      if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

      /* new home record will be a REC_RELOCATION and will be placed in the original home page */
      heap_build_forwarding_recdes (&new_home_recdes, REC_RELOCATION, &new_forward_oid);

      /* remove old forward record */
      remove_old_forward = true;
      update_old_home = true;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_REL_TO_REL_UPDATES);
    }
  else if (fits_in_home)
    {
      /* updated forward record fits in home page */
      context->recdes_p->type = REC_HOME;
      new_home_recdes = *context->recdes_p;

      /* remove old forward record */
      remove_old_forward = true;
      update_old_home = true;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_REL_TO_HOME_UPDATES);
    }
  else if (fits_in_forward)
    {
      /* updated forward record fits in old forward page */
      context->recdes_p->type = REC_NEWHOME;

      /* home record will not be touched */
      update_old_forward = true;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_REL_UPDATES);
    }
  else
    {
      /* impossible case */
      assert (false);
      rc = ER_FAILED;
      goto exit;
    }

  /* The old rec_newhome must be removed or updated */
  assert (remove_old_forward != update_old_forward);
  /* Remove rec_newhome only in case of old_home update */
  assert (remove_old_forward == update_old_home);

  /* 
   * Update old home record (if necessary)
   */
  if (update_old_home)
    {
      /* log operation */
      heap_log_update_physical (thread_p, context->home_page_watcher_p->pgptr, &context->hfid.vfid, &context->oid,
                &context->home_recdes, &new_home_recdes,
                (is_mvcc_op ? RVHF_UPDATE_NOTIFY_VACUUM : RVHF_UPDATE));
      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* update home record */
      rc = heap_update_physical (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid, &new_home_recdes);
      if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }
      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
    }

  /* 
   * Delete old forward record (if necessary)
   */
  if (remove_old_forward)
    {
      assert (context->forward_page_watcher_p != NULL && context->forward_page_watcher_p->pgptr != NULL);
      if ((new_home_recdes.type == REC_RELOCATION || new_home_recdes.type == REC_BIGONE)
      && context->forward_page_watcher_p->page_was_unfixed)
    {
      /* 
       * Need to get the record again, since the record may have changed by other concurrent
       * transactions (INSID removed by VACUUM).
       */
      if (spage_get_record (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid, &forward_recdes,
                COPY) != S_SUCCESS)
        {
          assert (false);
          ASSERT_ERROR_AND_SET (rc);
          goto exit;
        }
      HEAP_PERF_TRACK_PREPARE (thread_p, context);
    }


      /* log operation */
      heap_log_delete_physical (thread_p, context->forward_page_watcher_p->pgptr, &context->hfid.vfid, &forward_oid,
                &forward_recdes, true, &prev_version_lsa);
      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* physical removal of forward record */
      rc = heap_delete_physical (thread_p, &context->hfid, context->forward_page_watcher_p->pgptr, &forward_oid);
      if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }
      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
    }

  /* 
   * Update old forward record (if necessary)
   */
  if (update_old_forward)
    {
      /* log operation */
      heap_log_update_physical (thread_p, context->forward_page_watcher_p->pgptr, &context->hfid.vfid, &forward_oid,
                &forward_recdes, context->recdes_p, RVHF_UPDATE);
      LSA_COPY (&prev_version_lsa, logtb_find_current_tran_lsa (thread_p));

      if (is_mvcc_op)
    {
      LOG_DATA_ADDR p_addr;

      p_addr.pgptr = context->home_page_watcher_p->pgptr;
      p_addr.vfid = &context->hfid.vfid;
      p_addr.offset = context->oid.slotid;

      /* home remains untouched, log no_change on home to notify vacuum */
      heap_mvcc_log_home_no_change (thread_p, &p_addr);

      /* Even though home record is not modified, vacuum status of the page might be changed. */
      pgbuf_set_dirty (thread_p, context->home_page_watcher_p->pgptr, DONT_FREE);
    }

      HEAP_PERF_TRACK_LOGGING (thread_p, context);

      /* physical update of forward record */
      rc = heap_update_physical (thread_p, context->forward_page_watcher_p->pgptr, forward_oid.slotid,
                 context->recdes_p);
      if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

      HEAP_PERF_TRACK_EXECUTE (thread_p, context);
    }

  if (is_mvcc_op)
    {
      /* the updated record needs the prev version lsa to the undo log record where the old record can be found */
      rc = heap_update_set_prev_version (thread_p, &context->oid, context->home_page_watcher_p,
                     newhome_pg_watcher_p ? newhome_pg_watcher_p : context->forward_page_watcher_p,
                     &prev_version_lsa);

      if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }
    }

  /* location did not change */
  COPY_OID (&context->res_oid, &context->oid);

exit:

  if (newhome_pg_watcher_p != NULL && newhome_pg_watcher_p->pgptr != NULL)
    {
      /* newhome_pg_watcher is used only locally; must be unfixed */
      pgbuf_ordered_unfix (thread_p, newhome_pg_watcher_p);
    }

  return rc;
}

/*
 * heap_update_home () - update a REC_HOME record
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   is_mvcc_op(in): type of operation (MVCC/non-MVCC)
 */
static int
heap_update_home (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context, bool is_mvcc_op)
{
  int error_code = NO_ERROR;
  RECDES forwarding_recdes;
  RECDES *home_page_updated_recdes_p = NULL;
  OID forward_oid;
  LOG_RCVINDEX undo_rcvindex;
  LOG_LSA prev_version_lsa;
  PGBUF_WATCHER newhome_pg_watcher; /* fwd pg watcher required for heap_update_set_prev_version() */
  PGBUF_WATCHER *newhome_pg_watcher_p = NULL;

  assert (context != NULL);
  assert (context->recdes_p != NULL);
  assert (context->type == HEAP_OPERATION_UPDATE);
  assert (context->home_page_watcher_p != NULL);
  assert (context->home_page_watcher_p->pgptr != NULL);
  assert (context->forward_page_watcher_p != NULL);

  if (!HEAP_IS_UPDATE_INPLACE (context->update_in_place) && context->home_recdes.type == REC_ASSIGN_ADDRESS)
    {
      /* updating a REC_ASSIGN_ADDRESS should be done as a non-mvcc operation */
      assert (false);
#if defined(CUBRID_DEBUG)
      er_log_debug (ARG_FILE_LINE,
            "heap_update_home: ** SYSTEM_ERROR ** update"
            " mvcc update was attempted on REC_ASSIGN_ADDRESS home record");
#endif
      error_code = ER_FAILED;
      goto exit;
    }

#if defined (SERVER_MODE)
  if (is_mvcc_op)
    {
      undo_rcvindex = RVHF_UPDATE_NOTIFY_VACUUM;
    }
  else if (context->home_recdes.type == REC_ASSIGN_ADDRESS && !mvcc_is_mvcc_disabled_class (&context->class_oid))
    {
      /* Quick fix: Assign address is update in-place. Vacuum must be notified. */
      undo_rcvindex = RVHF_UPDATE_NOTIFY_VACUUM;
    }
  else
#endif /* SERVER_MODE */
    {
      undo_rcvindex = RVHF_UPDATE;
    }

  if (heap_is_big_length (context->recdes_p->length))
    {
      /* fix header page */
      error_code = heap_fix_header_page (thread_p, context);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

      /* insert new overflow record */
      HEAP_PERF_TRACK_PREPARE (thread_p, context);
      if (heap_ovf_insert (thread_p, &context->hfid, &forward_oid, context->recdes_p) == NULL)
    {
      ASSERT_ERROR_AND_SET (error_code);
      goto exit;
    }

      /* forwarding record is REC_BIGONE */
      heap_build_forwarding_recdes (&forwarding_recdes, REC_BIGONE, &forward_oid);

      /* we'll be updating home with forwarding record */
      home_page_updated_recdes_p = &forwarding_recdes;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_HOME_TO_BIG_UPDATES);
    }
  else if (!spage_is_updatable (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
                context->recdes_p->length))
    {
      /* insert new home */

      if (is_mvcc_op)
    {
      /* necessary later to set prev version, which is required only for mvcc objects */
      newhome_pg_watcher_p = &newhome_pg_watcher;
      PGBUF_INIT_WATCHER (newhome_pg_watcher_p, PGBUF_ORDERED_HEAP_NORMAL, PGBUF_ORDERED_NULL_HFID);
    }

      /* fix header page */
      error_code = heap_fix_header_page (thread_p, context);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

      /* insert new home record */
      HEAP_PERF_TRACK_PREPARE (thread_p, context);
      context->recdes_p->type = REC_NEWHOME;
      error_code = heap_insert_newhome (thread_p, context, context->recdes_p, &forward_oid, newhome_pg_watcher_p);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

      /* forwarding record is REC_RELOCATION */
      heap_build_forwarding_recdes (&forwarding_recdes, REC_RELOCATION, &forward_oid);

      /* we'll be updating home with forwarding record */
      home_page_updated_recdes_p = &forwarding_recdes;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_HOME_TO_REL_UPDATES);
    }
  else
    {
      context->recdes_p->type = REC_HOME;

      /* updated record fits in home page */
      home_page_updated_recdes_p = context->recdes_p;

      perfmon_inc_stat (thread_p, PSTAT_HEAP_HOME_UPDATES);
    }

  HEAP_PERF_TRACK_EXECUTE (thread_p, context);

  if ((home_page_updated_recdes_p->type == REC_RELOCATION || home_page_updated_recdes_p->type == REC_BIGONE)
      && context->home_page_watcher_p->page_was_unfixed)
    {
      /* 
       * Need to get the record again, since record may have changed
       * by other transactions (INSID removed by VACUUM, page compact).
       * The object was already locked, so the record size may be the
       * same or smaller (INSID removed by VACUUM). 
       */
      int is_peeking = (context->home_recdes.area_size >= context->home_recdes.length) ? COPY : PEEK;
      if (spage_get_record (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid, &context->home_recdes,
                is_peeking) != S_SUCCESS)
    {
      ASSERT_ERROR_AND_SET (error_code);
      goto exit;
    }
      HEAP_PERF_TRACK_PREPARE (thread_p, context);
    }

  /* log home update */
  heap_log_update_physical (thread_p, context->home_page_watcher_p->pgptr, &context->hfid.vfid, &context->oid,
                &context->home_recdes, home_page_updated_recdes_p, undo_rcvindex);
  LSA_COPY (&prev_version_lsa, logtb_find_current_tran_lsa (thread_p));

  HEAP_PERF_TRACK_LOGGING (thread_p, context);

  /* physical update of home record */
  error_code =
    heap_update_physical (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid,
              home_page_updated_recdes_p);
  if (error_code != NO_ERROR)
    {
      assert (false);
      ASSERT_ERROR ();
      goto exit;
    }

  if (is_mvcc_op)
    {
      /* the updated record needs the prev version lsa to the undo log record where the old record can be found */
      error_code = heap_update_set_prev_version (thread_p, &context->oid, context->home_page_watcher_p,
                         newhome_pg_watcher_p, &prev_version_lsa);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }
    }

  HEAP_PERF_TRACK_EXECUTE (thread_p, context);

  /* location did not change */
  COPY_OID (&context->res_oid, &context->oid);

  /* Fall through to exit. */

exit:

  if (newhome_pg_watcher_p != NULL && newhome_pg_watcher_p->pgptr != NULL)
    {
      /* newhome_pg_watcher is used only locally; must be unfixed */
      pgbuf_ordered_unfix (thread_p, newhome_pg_watcher_p);
    }

  return error_code;
}

/*
 * heap_update_physical () - physically update a record
 *   thread_p(in): thread entry
 *   page_p(in): page where record is stored
 *   slot_id(in): slot where record is stored within page
 *   recdes_p(in): record descriptor of updated record
 *   returns: error code or NO_ERROR
 */
static int
heap_update_physical (THREAD_ENTRY * thread_p, PAGE_PTR page_p, short slot_id, RECDES * recdes_p)
{
  int scancode;
  INT16 old_record_type;

  /* check input */
  assert (page_p != NULL);
  assert (recdes_p != NULL);
  assert (slot_id != NULL_SLOTID);

  /* retrieve current record type */
  old_record_type = spage_get_record_type (page_p, slot_id);

  /* update home page and check operation result */
  scancode = spage_update (thread_p, page_p, slot_id, recdes_p);
  if (scancode != SP_SUCCESS)
    {
      /* 
       * This is likely a system error since we have already checked
       * for space.
       */
      assert (false);
      if (scancode != SP_ERROR)
    {
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
    }

#if defined(CUBRID_DEBUG)
      er_log_debug (ARG_FILE_LINE,
            "heap_update_physical: ** SYSTEM_ERROR ** update operation failed even when have already checked"
            " for space");
#endif

      return ER_FAILED;
    }

  /* Reflect record type change */
  if (old_record_type != recdes_p->type)
    {
      spage_update_record_type (thread_p, page_p, slot_id, recdes_p->type);
    }

  /* mark as dirty */
  pgbuf_set_dirty (thread_p, page_p, DONT_FREE);

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_log_update_physical () - log a physical update
 *   thread_p(in): thread entry
 *   page_p(in): updated page
 *   vfid_p(in): virtual file id
 *   oid_p(in): object id
 *   old_recdes_p(in): old record
 *   new_recdes_p(in): new record
 *   rcvindex(in): Index to recovery function
 */
static void
heap_log_update_physical (THREAD_ENTRY * thread_p, PAGE_PTR page_p, VFID * vfid_p, OID * oid_p, RECDES * old_recdes_p,
              RECDES * new_recdes_p, LOG_RCVINDEX rcvindex)
{
  LOG_DATA_ADDR address;

  /* build address */
  address.offset = oid_p->slotid;
  address.pgptr = page_p;
  address.vfid = vfid_p;

  /* actual logging */
  if (LOG_IS_MVCC_HEAP_OPERATION (rcvindex))
    {
      HEAP_PAGE_VACUUM_STATUS vacuum_status = heap_page_get_vacuum_status (thread_p, page_p);
      heap_page_update_chain_after_mvcc_op (thread_p, page_p, logtb_get_current_mvccid (thread_p));
      if (heap_page_get_vacuum_status (thread_p, page_p) != vacuum_status)
    {
      /* Mark vacuum status change for recovery. */
      address.offset |= HEAP_RV_FLAG_VACUUM_STATUS_CHANGE;
    }
    }

  log_append_undoredo_recdes (thread_p, rcvindex, &address, old_recdes_p, new_recdes_p);
}

/*
 * heap_create_insert_context () - create an insertion context
 *   context(in): context to set up
 *   hfid_p(in): heap file identifier
 *   class_oid_p(in): class OID
 *   recdes_p(in): record descriptor to insert
 *   scancache_p(in): scan cache to use (optional)
 */
void
heap_create_insert_context (HEAP_OPERATION_CONTEXT * context, HFID * hfid_p, OID * class_oid_p, RECDES * recdes_p,
                HEAP_SCANCACHE * scancache_p)
{
  assert (context != NULL);
  assert (hfid_p != NULL);
  assert (recdes_p != NULL);

  heap_clear_operation_context (context, hfid_p);
  if (class_oid_p != NULL)
    {
      COPY_OID (&context->class_oid, class_oid_p);
    }
  context->recdes_p = recdes_p;
  context->scan_cache_p = scancache_p;
  context->type = HEAP_OPERATION_INSERT;
}

/*
 * heap_create_delete_context () - create a deletion context
 *   context(in): context to set up
 *   hfid_p(in): heap file identifier
 *   oid(in): identifier of object to delete
 *   class_oid_p(in): class OID
 *   scancache_p(in): scan cache to use (optional)
 */
void
heap_create_delete_context (HEAP_OPERATION_CONTEXT * context, HFID * hfid_p, OID * oid_p, OID * class_oid_p,
                HEAP_SCANCACHE * scancache_p)
{
  assert (context != NULL);
  assert (hfid_p != NULL);
  assert (oid_p != NULL);
  assert (class_oid_p != NULL);

  heap_clear_operation_context (context, hfid_p);
  COPY_OID (&context->oid, oid_p);
  COPY_OID (&context->class_oid, class_oid_p);
  context->scan_cache_p = scancache_p;
  context->type = HEAP_OPERATION_DELETE;
}

/*
 * heap_create_update_context () - create an update operation context
 *   context(in): context to set up
 *   hfid_p(in): heap file identifier
 *   oid(in): identifier of object to delete
 *   class_oid_p(in): class OID
 *   recdes_p(in): updated record to write
 *   scancache_p(in): scan cache to use (optional)
 *   in_place(in): specifies if the "in place" type of the update operation
 */
void
heap_create_update_context (HEAP_OPERATION_CONTEXT * context, HFID * hfid_p, OID * oid_p, OID * class_oid_p,
                RECDES * recdes_p, HEAP_SCANCACHE * scancache_p, UPDATE_INPLACE_STYLE in_place)
{
  assert (context != NULL);
  assert (hfid_p != NULL);
  assert (oid_p != NULL);
  assert (class_oid_p != NULL);
  assert (recdes_p != NULL);

  heap_clear_operation_context (context, hfid_p);
  COPY_OID (&context->oid, oid_p);
  COPY_OID (&context->class_oid, class_oid_p);
  context->recdes_p = recdes_p;
  context->scan_cache_p = scancache_p;
  context->type = HEAP_OPERATION_UPDATE;
  context->update_in_place = in_place;
}

/*
 * heap_insert_logical () - Insert an object onto heap
 *   context(in/out): operation context
 *   return: error code or NO_ERROR
 *
 * Note: Insert an object onto the given file heap. The object is
 * inserted using the following algorithm:
 *              1: If the object cannot be inserted in a single page, it is
 *                 inserted in overflow as a multipage object. An overflow
 *                 relocation record is created in the heap as an address map
 *                 to the actual content of the object (the overflow address).
 *              2: If the object can be inserted in the last allocated page
 *                 without overpassing the reserved space on the page, the
 *                 object is placed on this page.
 *              3: If the object can be inserted in the hinted page without
 *                 overpassing the reserved space on the page, the object is
 *             placed on this page.
 *              4: The object is inserted in a newly allocated page. Don't
 *                 about reserve space here.
 *
 * NOTE-1: The class object was already IX-locked during compile time
 *         under normal situation.
 *         However, with prepare-execute-commit-execute-... scenario,
 *         the class object is not properly IX-locked since the previous
 *         commit released the entire acquired locks including IX-lock.
 *         So we have to make it sure the class object is IX-locked at this
 *         moment.
 */
int
heap_insert_logical (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  bool is_mvcc_op;
  int rc = NO_ERROR;
  PERF_UTIME_TRACKER time_track;
  bool is_mvcc_class;

  /* check required input */
  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_INSERT);
  assert (context->recdes_p != NULL);
  assert (!HFID_IS_NULL (&context->hfid));

  context->time_track = &time_track;
  HEAP_PERF_START (thread_p, context);

  /* check scancache */
  if (heap_scancache_check_with_hfid (thread_p, &context->hfid, &context->class_oid, &context->scan_cache_p) !=
      NO_ERROR)
    {
      return ER_FAILED;
    }

  is_mvcc_class = !mvcc_is_mvcc_disabled_class (&context->class_oid);
  /* 
   * Determine type of operation
   */
#if defined (SERVER_MODE)
  if (is_mvcc_class && context->recdes_p->type != REC_ASSIGN_ADDRESS)
    {
      is_mvcc_op = true;
    }
  else
    {
      is_mvcc_op = false;
    }
#else /* SERVER_MODE */
  is_mvcc_op = false;
#endif /* SERVER_MODE */

  /* 
   * Record header adjustments
   */
  if (!OID_ISNULL (&context->class_oid) && !OID_IS_ROOTOID (&context->class_oid)
      && context->recdes_p->type != REC_ASSIGN_ADDRESS)
    {
      if (heap_insert_adjust_recdes_header (thread_p, context, is_mvcc_class) != NO_ERROR)
    {
      return ER_FAILED;
    }
    }

#if defined(ENABLE_SYSTEMTAP)
  CUBRID_OBJ_INSERT_START (&context->class_oid);
#endif /* ENABLE_SYSTEMTAP */

  /* 
   * Handle multipage object
   */
  if (heap_insert_handle_multipage_record (thread_p, context) != NO_ERROR)
    {
      rc = ER_FAILED;
      goto error;
    }

  /* 
   * Locking
   */
  /* make sure we have IX_LOCK on class see [NOTE-1] */
  if (lock_object (thread_p, &context->class_oid, oid_Root_class_oid, IX_LOCK, LK_UNCOND_LOCK) != LK_GRANTED)
    {
      return ER_FAILED;
    }

  /* get insert location (includes locking) */
  if (heap_get_insert_location_with_lock (thread_p, context, NULL) != NO_ERROR)
    {
      return ER_FAILED;
    }

  HEAP_PERF_TRACK_PREPARE (thread_p, context);

  /* 
   * Physical insertion
   */
  if (heap_insert_physical (thread_p, context) != NO_ERROR)
    {
      rc = ER_FAILED;
      goto error;
    }

  HEAP_PERF_TRACK_EXECUTE (thread_p, context);

  /* 
   * Operation logging
   */
  heap_log_insert_physical (thread_p, context->home_page_watcher_p->pgptr, &context->hfid.vfid, &context->res_oid,
                context->recdes_p, is_mvcc_op, context->is_redistribute_insert_with_delid);

  HEAP_PERF_TRACK_LOGGING (thread_p, context);

  /* mark insert page as dirty */
  pgbuf_set_dirty (thread_p, context->home_page_watcher_p->pgptr, DONT_FREE);

  /* 
   * Page unfix or caching
   */
  if (context->scan_cache_p != NULL && context->home_page_watcher_p == &context->home_page_watcher
      && context->scan_cache_p->cache_last_fix_page == true)
    {
      /* cache */
      assert (context->home_page_watcher_p->pgptr != NULL);
      pgbuf_replace_watcher (thread_p, context->home_page_watcher_p, &context->scan_cache_p->page_watcher);
    }
  else
    {
      /* unfix */
      pgbuf_ordered_unfix (thread_p, context->home_page_watcher_p);
    }

  /* unfix other pages */
  heap_unfix_watchers (thread_p, context);

  /* 
   * Class creation case
   */
  if (context->recdes_p->type != REC_ASSIGN_ADDRESS && HFID_EQ ((&context->hfid), &(heap_Classrepr->rootclass_hfid)))
    {
      if (heap_mark_class_as_modified (thread_p, &context->res_oid, or_chn (context->recdes_p), false) != NO_ERROR)
    {
      rc = ER_FAILED;
      goto error;
    }
    }

  if (context->recdes_p->type == REC_HOME)
    {
      perfmon_inc_stat (thread_p, PSTAT_HEAP_HOME_INSERTS);
    }
  else if (context->recdes_p->type == REC_BIGONE)
    {
      perfmon_inc_stat (thread_p, PSTAT_HEAP_BIG_INSERTS);
    }
  else
    {
      perfmon_inc_stat (thread_p, PSTAT_HEAP_ASSIGN_INSERTS);
    }

error:

#if defined(ENABLE_SYSTEMTAP)
  CUBRID_OBJ_INSERT_END (&context->class_oid, (rc < 0));
#endif /* ENABLE_SYSTEMTAP */

  /* all ok */
  return rc;
}

/*
 * heap_delete_logical () - Delete an object from heap file
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   return: error code or NO_ERROR
 *
 * Note: Delete the object associated with the given OID from the given
 * heap file. If the object has been relocated or stored in
 * overflow, both the relocation and the relocated record are deleted.
 */
int
heap_delete_logical (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  bool is_mvcc_op;
  int rc = NO_ERROR;
  PERF_UTIME_TRACKER time_track;

  /* 
   * Check input
   */
  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_DELETE);
  assert (!HFID_IS_NULL (&context->hfid));
  assert (!OID_ISNULL (&context->oid));

  context->time_track = &time_track;
  HEAP_PERF_START (thread_p, context);

  /* check input OID validity */
  if (heap_is_valid_oid (thread_p, &context->oid) != NO_ERROR)
    {
      return ER_FAILED;
    }

  /* check scancache */
  if (heap_scancache_check_with_hfid (thread_p, &context->hfid, &context->class_oid, &context->scan_cache_p) !=
      NO_ERROR)
    {
      return ER_FAILED;
    }

  /* check file type */
  context->file_type = heap_get_file_type (thread_p, context);
  if (context->file_type != FILE_HEAP && context->file_type != FILE_HEAP_REUSE_SLOTS)
    {
      if (context->file_type == FILE_UNKNOWN_TYPE)
    {
      ASSERT_ERROR_AND_SET (rc);
      if (rc == ER_INTERRUPTED)
        {
          return rc;
        }
    }
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      return ER_FAILED;
    }

  /* 
   * Class deletion case
   */
  if (HFID_EQ (&context->hfid, &(heap_Classrepr->rootclass_hfid)))
    {
      if (heap_mark_class_as_modified (thread_p, &context->oid, NULL_CHN, true) != NO_ERROR)
    {
      return ER_FAILED;
    }
    }

  /* 
   * Determine type of operation
   */
#if defined (SERVER_MODE)
  if (mvcc_is_mvcc_disabled_class (&context->class_oid))
    {
      is_mvcc_op = false;
    }
  else
    {
      is_mvcc_op = true;
    }
#else /* SERVER_MODE */
  is_mvcc_op = false;
#endif /* SERVER_MODE */

#if defined(ENABLE_SYSTEMTAP)
  CUBRID_OBJ_DELETE_START (&context->class_oid);
#endif /* ENABLE_SYSTEMTAP */

  /* 
   * Fetch object's page and check record type
   */
  if (heap_get_record_location (thread_p, context) != NO_ERROR)
    {
      rc = ER_FAILED;
      goto error;
    }

  context->record_type = spage_get_record_type (context->home_page_watcher_p->pgptr, context->oid.slotid);
  if (context->record_type == REC_UNKNOWN)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, context->oid.volid, context->oid.pageid,
          context->oid.slotid);
      rc = ER_FAILED;
      goto error;
    }

  /* fetch record to be deleted */
  context->home_recdes.area_size = DB_PAGESIZE;
  context->home_recdes.data = PTR_ALIGN (context->home_recdes_buffer, MAX_ALIGNMENT);
  if (spage_get_record (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid, &context->home_recdes, COPY)
      != S_SUCCESS)
    {
      rc = ER_FAILED;
      goto error;
    }

  HEAP_PERF_TRACK_PREPARE (thread_p, context);

  /* 
   * Physical deletion and logging
   */
  switch (context->record_type)
    {
    case REC_BIGONE:
      rc = heap_delete_bigone (thread_p, context, is_mvcc_op);
      break;

    case REC_RELOCATION:
      rc = heap_delete_relocation (thread_p, context, is_mvcc_op);
      break;

    case REC_HOME:
    case REC_ASSIGN_ADDRESS:
      rc = heap_delete_home (thread_p, context, is_mvcc_op);
      break;

    default:
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_BAD_OBJECT_TYPE, 3, context->oid.volid, context->oid.pageid,
          context->oid.slotid);
      rc = ER_FAILED;
      goto error;
    }


error:

  /* unfix or keep home page */
  if (context->scan_cache_p != NULL && context->home_page_watcher_p == &context->home_page_watcher
      && context->scan_cache_p->cache_last_fix_page == true)
    {
      pgbuf_replace_watcher (thread_p, context->home_page_watcher_p, &context->scan_cache_p->page_watcher);
    }
  else
    {
      if (context->home_page_watcher_p->pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, context->home_page_watcher_p);
    }
    }

  /* unfix pages */
  heap_unfix_watchers (thread_p, context);

#if defined(ENABLE_SYSTEMTAP)
  CUBRID_OBJ_DELETE_END (&context->class_oid, (rc != NO_ERROR));
#endif /* ENABLE_SYSTEMTAP */

  return rc;
}

/*
 * heap_update_logical () - update a record in a heap file
 *   thread_p(in): thread entry
 *   context(in): operation context
 *   return: error code or NO_ERROR
 */
extern int
heap_update_logical (THREAD_ENTRY * thread_p, HEAP_OPERATION_CONTEXT * context)
{
  bool is_mvcc_op;
  int rc = NO_ERROR;
  PERF_UTIME_TRACKER time_track;
  bool is_mvcc_class;

  /* 
   * Check input
   */
  assert (context != NULL);
  assert (context->type == HEAP_OPERATION_UPDATE);
  assert (!OID_ISNULL (&context->oid));
  assert (!OID_ISNULL (&context->class_oid));

  context->time_track = &time_track;
  HEAP_PERF_START (thread_p, context);

  /* check scancache */
  rc = heap_scancache_check_with_hfid (thread_p, &context->hfid, &context->class_oid, &context->scan_cache_p);
  if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      return rc;
    }

  /* check file type */
  context->file_type = heap_get_file_type (thread_p, context);
  if (context->file_type != FILE_HEAP && context->file_type != FILE_HEAP_REUSE_SLOTS)
    {
      if (context->file_type == FILE_UNKNOWN_TYPE)
    {
      ASSERT_ERROR_AND_SET (rc);
      if (rc == ER_INTERRUPTED)
        {
          return rc;
        }
    }
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      return ER_GENERIC_ERROR;
    }

  /* get heap file identifier from scancache if none was provided */
  if (HFID_IS_NULL (&context->hfid))
    {
      if (context->scan_cache_p != NULL)
    {
      HFID_COPY (&context->hfid, &context->scan_cache_p->node.hfid);
    }
      else
    {
      er_log_debug (ARG_FILE_LINE, "heap_update: Bad interface a heap is needed");
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_HEAP, 3, "", NULL_FILEID, NULL_PAGEID);
      assert (false);
      return ER_HEAP_UNKNOWN_HEAP;
    }
    }

  /* check provided object identifier */
  rc = heap_is_valid_oid (thread_p, &context->oid);
  if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      return rc;
    }

  /* by default, consider it old */
  context->is_logical_old = true;

  is_mvcc_class = !mvcc_is_mvcc_disabled_class (&context->class_oid);
  /* 
   * Determine type of operation
   */
  is_mvcc_op = HEAP_UPDATE_IS_MVCC_OP (is_mvcc_class, context->update_in_place);
#if defined (SERVER_MODE)
  assert ((!is_mvcc_op && HEAP_IS_UPDATE_INPLACE (context->update_in_place))
      || (is_mvcc_op && !HEAP_IS_UPDATE_INPLACE (context->update_in_place)));
  /* the update in place concept should be changed in terms of mvcc */
#endif /* SERVER_MODE */

#if defined(ENABLE_SYSTEMTAP)
  CUBRID_OBJ_UPDATE_START (&context->class_oid);
#endif /* ENABLE_SYSTEMTAP */

  /* 
   * Get location
   */
  rc = heap_get_record_location (thread_p, context);
  if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

  /* decache guessed representation */
  HEAP_MAYNEED_DECACHE_GUESSED_LASTREPRS (&context->oid, &context->hfid);

  /* 
   * Fetch record
   */
  context->record_type = spage_get_record_type (context->home_page_watcher_p->pgptr, context->oid.slotid);
  if (context->record_type == REC_UNKNOWN)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, context->oid.volid, context->oid.pageid,
          context->oid.slotid);
      rc = ER_HEAP_UNKNOWN_OBJECT;
      goto exit;
    }

  context->home_recdes.area_size = DB_PAGESIZE;
  context->home_recdes.data = PTR_ALIGN (context->home_recdes_buffer, MAX_ALIGNMENT);
  if (spage_get_record (thread_p, context->home_page_watcher_p->pgptr, context->oid.slotid, &context->home_recdes, COPY)
      != S_SUCCESS)
    {
      rc = ER_FAILED;
      goto exit;
    }

  /* 
   * Adjust new record header
   */
  if (!OID_ISNULL (&context->class_oid) && !OID_IS_ROOTOID (&context->class_oid))
    {
      rc = heap_update_adjust_recdes_header (thread_p, context, is_mvcc_class);
      if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }
    }

  HEAP_PERF_TRACK_PREPARE (thread_p, context);

  /* 
   * Update record
   */
  switch (context->record_type)
    {
    case REC_RELOCATION:
      rc = heap_update_relocation (thread_p, context, is_mvcc_op);
      break;

    case REC_BIGONE:
      rc = heap_update_bigone (thread_p, context, is_mvcc_op);
      break;

    case REC_ASSIGN_ADDRESS:
      /* it's not an old record, it was inserted in this transaction */
      context->is_logical_old = false;
      /* fall trough */
    case REC_HOME:
      rc = heap_update_home (thread_p, context, is_mvcc_op);
      break;

    default:
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_BAD_OBJECT_TYPE, 3, context->oid.volid, context->oid.pageid,
          context->oid.slotid);
      rc = ER_HEAP_BAD_OBJECT_TYPE;
      goto exit;
    }

  /* check return code of operation */
  if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }

  /* 
   * Class update case
   */
  if (HFID_EQ ((&context->hfid), &(heap_Classrepr->rootclass_hfid)))
    {
      rc = heap_mark_class_as_modified (thread_p, &context->oid, or_chn (context->recdes_p), false);
      if (rc != NO_ERROR)
    {
      ASSERT_ERROR ();
      goto exit;
    }
    }

exit:

  /* unfix or cache home page */
  if (context->home_page_watcher_p->pgptr != NULL && context->home_page_watcher_p == &context->home_page_watcher)
    {
      if (context->scan_cache_p != NULL && context->scan_cache_p->cache_last_fix_page)
    {
      pgbuf_replace_watcher (thread_p, context->home_page_watcher_p, &context->scan_cache_p->page_watcher);
    }
      else
    {
      pgbuf_ordered_unfix (thread_p, context->home_page_watcher_p);
    }
    }

  /* unfix pages */
  heap_unfix_watchers (thread_p, context);

#if defined(ENABLE_SYSTEMTAP)
  CUBRID_OBJ_UPDATE_END (&context->class_oid, (rc != NO_ERROR));
#endif /* ENABLE_SYSTEMTAP */

  return rc;
}

/*
 * heap_get_hfid_from_class_record () - get HFID from class record for the
 *                    given OID.
 *   return: error_code
 *   class_oid(in): class oid
 *   hfid(out):  the resulting hfid
 */
static int
heap_get_hfid_from_class_record (THREAD_ENTRY * thread_p, const OID * class_oid, HFID * hfid)
{
  int error_code = NO_ERROR;
  RECDES recdes;
  HEAP_SCANCACHE scan_cache;

  if (class_oid == NULL || hfid == NULL)
    {
      return ER_FAILED;
    }

  (void) heap_scancache_quick_start_root_hfid (thread_p, &scan_cache);

  if (heap_get_class_record (thread_p, class_oid, &recdes, &scan_cache, PEEK) != S_SUCCESS)
    {
      heap_scancache_end (thread_p, &scan_cache);
      return ER_FAILED;
    }

  or_class_hfid (&recdes, hfid);

  error_code = heap_scancache_end (thread_p, &scan_cache);
  if (error_code != NO_ERROR)
    {
      return error_code;
    }

  return error_code;
}

/*
 * heap_hfid_table_entry_alloc() - allocate a new structure for
 *        the class OID->HFID hash
 *   returns: new pointer or NULL on error
 */
static void *
heap_hfid_table_entry_alloc (void)
{
  HEAP_HFID_TABLE_ENTRY *new_entry = (HEAP_HFID_TABLE_ENTRY *) malloc (sizeof (HEAP_HFID_TABLE_ENTRY));
  return (void *) new_entry;
}

/*
 * logtb_global_unique_stat_free () - free a hfid_table entry
 *   returns: error code or NO_ERROR
 *   entry(in): entry to free (HEAP_HFID_TABLE_ENTRY)
 */
static int
heap_hfid_table_entry_free (void *entry)
{
  if (entry != NULL)
    {
      free (entry);
      return NO_ERROR;
    }
  else
    {
      return ER_FAILED;
    }
}

/*
 * heap_hfid_table_entry_init () - initialize a hfid_table entry
 *   returns: error code or NO_ERROR
 *   entry(in): hfid_table entry
 */
static int
heap_hfid_table_entry_init (void *entry)
{
  HEAP_HFID_TABLE_ENTRY *entry_p = (HEAP_HFID_TABLE_ENTRY *) entry;

  if (entry_p == NULL)
    {
      return ER_FAILED;
    }

  /* initialize fields */
  OID_SET_NULL (&entry_p->class_oid);
  entry_p->hfid.vfid.fileid = NULL_FILEID;
  entry_p->hfid.vfid.volid = NULL_VOLID;
  entry_p->hfid.hpgid = NULL_PAGEID;
  entry_p->ftype = FILE_UNKNOWN_TYPE;

  return NO_ERROR;
}

/*
 * heap_hfid_table_entry_key_copy () - copy a hfid_table key
 *   returns: error code or NO_ERROR
 *   src(in): source
 *   dest(in): destination
 */
static int
heap_hfid_table_entry_key_copy (void *src, void *dest)
{
  if (src == NULL || dest == NULL)
    {
      return ER_FAILED;
    }

  COPY_OID ((OID *) dest, (OID *) src);

  /* all ok */
  return NO_ERROR;
}

/*
 * heap_hfid_table_entry_key_hash () - hashing function for the class OID->HFID
 *                  hash table
 *   return: int
 *   key(in): Session key
 *   hash_table_size(in): Memory Hash Table Size
 *
 * Note: Generate a hash number for the given key for the given hash table
 *   size.
 */
static unsigned int
heap_hfid_table_entry_key_hash (void *key, int hash_table_size)
{
  return ((unsigned int) OID_PSEUDO_KEY ((OID *) key)) % hash_table_size;
}

/*
 * heap_hfid_table_entry_key_compare () - Compare two global unique
 *                       statistics keys (OIDs)
 *   return: int (true or false)
 *   k1  (in) : First OID key
 *   k2 (in) : Second OID key
 */
static int
heap_hfid_table_entry_key_compare (void *k1, void *k2)
{
  OID *key1, *key2;

  key1 = (OID *) k1;
  key2 = (OID *) k2;

  if (k1 == NULL || k2 == NULL)
    {
      /* should not happen */
      assert (false);
      return 0;
    }

  if (OID_EQ (key1, key2))
    {
      /* equal */
      return 0;
    }
  else
    {
      /* not equal */
      return 1;
    }
}

/*
 * heap_initialize_hfid_table () - Creates and initializes global structure
 *                  for global class OID->HFID hash table
 *   return: error code
 *   thread_p  (in) : 
 */
int
heap_initialize_hfid_table (void)
{
  int ret = NO_ERROR;
  LF_ENTRY_DESCRIPTOR *edesc = NULL;

  if (heap_Hfid_table != NULL)
    {
      return NO_ERROR;
    }

  edesc = &heap_Hfid_table_area.hfid_hash_descriptor;

  edesc->of_local_next = offsetof (HEAP_HFID_TABLE_ENTRY, stack);
  edesc->of_next = offsetof (HEAP_HFID_TABLE_ENTRY, next);
  edesc->of_del_tran_id = offsetof (HEAP_HFID_TABLE_ENTRY, del_id);
  edesc->of_key = offsetof (HEAP_HFID_TABLE_ENTRY, class_oid);
  edesc->of_mutex = 0;
  edesc->using_mutex = LF_EM_NOT_USING_MUTEX;
  edesc->f_alloc = heap_hfid_table_entry_alloc;
  edesc->f_free = heap_hfid_table_entry_free;
  edesc->f_init = heap_hfid_table_entry_init;
  edesc->f_uninit = NULL;
  edesc->f_key_copy = heap_hfid_table_entry_key_copy;
  edesc->f_key_cmp = heap_hfid_table_entry_key_compare;
  edesc->f_hash = heap_hfid_table_entry_key_hash;
  edesc->f_duplicate = NULL;

  /* initialize freelist */
  ret = lf_freelist_init (&heap_Hfid_table_area.hfid_hash_freelist, 1, 100, edesc, &hfid_table_Ts);
  if (ret != NO_ERROR)
    {
      return ret;
    }

  /* initialize hash table */
  ret =
    lf_hash_init (&heap_Hfid_table_area.hfid_hash, &heap_Hfid_table_area.hfid_hash_freelist, HEAP_HFID_HASH_SIZE,
          edesc);
  if (ret != NO_ERROR)
    {
      lf_hash_destroy (&heap_Hfid_table_area.hfid_hash);
      return ret;
    }

  heap_Hfid_table = &heap_Hfid_table_area;

  return ret;
}

/*
 * heap_finalize_hfid_table () - Finalize class OID->HFID hash table
 *   return: error code
 *   thread_p  (in) : 
 */
void
heap_finalize_hfid_table (void)
{
  if (heap_Hfid_table != NULL)
    {
      /* destroy hash and freelist */
      lf_hash_destroy (&heap_Hfid_table->hfid_hash);
      lf_freelist_destroy (&heap_Hfid_table->hfid_hash_freelist);

      heap_Hfid_table = NULL;
    }
}

/*
 * heap_delete_hfid_from_cache () - deletes the entry associated with
 *                  the given class OID from the hfid table
 *   return: error code
 *   thread_p  (in) :
 *   class_oid (in) : the class OID for which the entry will be deleted
 */
int
heap_delete_hfid_from_cache (THREAD_ENTRY * thread_p, OID * class_oid)
{
  LF_TRAN_ENTRY *t_entry = thread_get_tran_entry (thread_p, THREAD_TS_HFID_TABLE);
  int error = NO_ERROR;

  error = lf_hash_delete (t_entry, &heap_Hfid_table->hfid_hash, class_oid, NULL);
  if (error != NO_ERROR)
    {
      return error;
    }

  return NO_ERROR;
}

/*
 * heap_vacuum_all_objects () - Vacuum all objects in heap.
 *
 * return        : Error code.
 * thread_p (in)     : Thread entry.
 * upd_scancache(in)     : Update scan cache
 * threshold_mvccid(in)  : Threshold MVCCID
 */
int
heap_vacuum_all_objects (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * upd_scancache, MVCCID threshold_mvccid)
{
  PGBUF_WATCHER pg_watcher;
  PGBUF_WATCHER old_pg_watcher;
  VPID next_vpid, vpid;
  VACUUM_WORKER worker;
  int max_num_slots, i;
  OID temp_oid;
  bool reusable;
  int error_code = NO_ERROR;

  assert (upd_scancache != NULL);
  PGBUF_INIT_WATCHER (&pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, &upd_scancache->node.hfid);
  PGBUF_INIT_WATCHER (&old_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, &upd_scancache->node.hfid);
  memset (&worker, 0, sizeof (worker));
  max_num_slots = IO_MAX_PAGE_SIZE / sizeof (SPAGE_SLOT);
  worker.heap_objects = (VACUUM_HEAP_OBJECT *) malloc (max_num_slots * sizeof (VACUUM_HEAP_OBJECT));
  if (worker.heap_objects == NULL)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1,
          max_num_slots * sizeof (VACUUM_HEAP_OBJECT));
      error_code = ER_OUT_OF_VIRTUAL_MEMORY;
      goto exit;
    }
  worker.heap_objects_capacity = max_num_slots;
  worker.n_heap_objects = 0;

  next_vpid.volid = upd_scancache->node.hfid.vfid.volid;
  next_vpid.pageid = upd_scancache->node.hfid.hpgid;
  for (i = 0; i < max_num_slots; i++)
    {
      VFID_COPY (&worker.heap_objects[i].vfid, &upd_scancache->node.hfid.vfid);
    }

  reusable = heap_is_reusable_oid (upd_scancache->file_type);
  while (!VPID_ISNULL (&next_vpid))
    {
      vpid = next_vpid;
      error_code = pgbuf_ordered_fix (thread_p, &vpid, OLD_PAGE, PGBUF_LATCH_WRITE, &pg_watcher);
      if (error_code != NO_ERROR)
    {
      goto exit;
    }

      (void) pgbuf_check_page_ptype (thread_p, pg_watcher.pgptr, PAGE_HEAP);

      if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }

      error_code = heap_vpid_next (thread_p, &upd_scancache->node.hfid, pg_watcher.pgptr, &next_vpid);
      if (error_code != NO_ERROR)
    {
      assert (false);
      goto exit;
    }

      temp_oid.volid = vpid.volid;
      temp_oid.pageid = vpid.pageid;
      worker.n_heap_objects = spage_number_of_slots (pg_watcher.pgptr) - 1;
      if (worker.n_heap_objects > 0
      && heap_page_get_vacuum_status (thread_p, pg_watcher.pgptr) != HEAP_PAGE_VACUUM_NONE)
    {
      for (i = 1; i <= worker.n_heap_objects; i++)
        {
          temp_oid.slotid = i;
          COPY_OID (&worker.heap_objects[i - 1].oid, &temp_oid);
        }

      error_code =
        vacuum_heap_page (thread_p, worker.heap_objects, worker.n_heap_objects, threshold_mvccid,
                  &upd_scancache->node.hfid, &reusable, false);
      if (error_code != NO_ERROR)
        {
          goto exit;
        }
    }

      pgbuf_replace_watcher (thread_p, &pg_watcher, &old_pg_watcher);
    }

exit:
  if (pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &pg_watcher);
    }
  if (old_pg_watcher.pgptr != NULL)
    {
      pgbuf_ordered_unfix (thread_p, &old_pg_watcher);
    }

  if (worker.heap_objects != NULL)
    {
      free_and_init (worker.heap_objects);
    }
  return error_code;
}

/*
 * heap_insert_hfid_for_class_oid () - Cache HFID for class object.
 *
 * return     : Error code.
 * thread_p (in)  : Thread entry.
 * class_oid (in) : Class OID.
 * hfid (in)      : Heap file ID.
 * ftype (in)     : FILE_HEAP or FILE_HEAP_REUSE_SLOTS.
 */
int
heap_insert_hfid_for_class_oid (THREAD_ENTRY * thread_p, const OID * class_oid, HFID * hfid, FILE_TYPE ftype)
{
  int error_code = NO_ERROR;
  LF_TRAN_ENTRY *t_entry = thread_get_tran_entry (thread_p, THREAD_TS_HFID_TABLE);
  HEAP_HFID_TABLE_ENTRY *entry = NULL;

  assert (hfid != NULL && !HFID_IS_NULL (hfid));
  assert (ftype == FILE_HEAP || ftype == FILE_HEAP_REUSE_SLOTS);

  if (class_oid == NULL || OID_ISNULL (class_oid))
    {
      /* We can't cache it. */
      return NO_ERROR;
    }

  error_code =
    lf_hash_find_or_insert (t_entry, &heap_Hfid_table->hfid_hash, (void *) class_oid, (void **) &entry, NULL);
  if (error_code != NO_ERROR)
    {
      return error_code;
    }
  assert (entry != NULL);
  assert (entry->hfid.hpgid == NULL_PAGEID);

  HFID_COPY (&entry->hfid, hfid);
  entry->ftype = ftype;
  lf_tran_end_with_mb (t_entry);

  /* Successfully cached. */
  return NO_ERROR;
}

/*
 * heap_hfid_cache_get () - returns the HFID of the
 *                class with the given class OID
 *   return: error code
 *   thread_p  (in) :
 *   class OID (in) : the class OID for which the entry will be returned
 *   hfid_out  (out): 
 *
 *   Note: if the entry is not found, one will be inserted and the HFID is
 *  retrieved from the class record.
 */
static int
heap_hfid_cache_get (THREAD_ENTRY * thread_p, const OID * class_oid, HFID * hfid_out, FILE_TYPE * ftype_out)
{
  int error_code = NO_ERROR;
  LF_TRAN_ENTRY *t_entry = thread_get_tran_entry (thread_p, THREAD_TS_HFID_TABLE);
  HEAP_HFID_TABLE_ENTRY *entry = NULL;

  assert (class_oid != NULL && !OID_ISNULL (class_oid));

  error_code =
    lf_hash_find_or_insert (t_entry, &heap_Hfid_table->hfid_hash, (void *) class_oid, (void **) &entry, NULL);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      return error_code;
    }
  assert (entry != NULL);


  if (entry->hfid.hpgid == NULL_PAGEID || entry->hfid.vfid.fileid == NULL_FILEID
      || entry->hfid.vfid.volid == NULL_VOLID)
    {
      HFID hfid_local = HFID_INITIALIZER;

      /* root HFID should already be added. */
      if (OID_IS_ROOTOID (class_oid))
    {
      assert_release (false);
      boot_find_root_heap (&entry->hfid);
      entry->ftype = FILE_HEAP;
      lf_tran_end_with_mb (t_entry);
      return NO_ERROR;
    }

      /* this is either a newly inserted entry or one with incomplete information that is currently being filled by
       * another transaction. We need to retrieve the HFID from the class record. We do not care that we are
       * overwriting the information, since it must be always the same (the HFID never changes for the same class OID). */
      error_code = heap_get_hfid_from_class_record (thread_p, class_oid, &hfid_local);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      lf_tran_end_with_mb (t_entry);
      return error_code;
    }
      entry->hfid = hfid_local;
    }
  assert (entry->hfid.hpgid != NULL_PAGEID && entry->hfid.vfid.fileid != NULL_FILEID
      && entry->hfid.vfid.volid != NULL_VOLID);
  if (entry->ftype == FILE_UNKNOWN_TYPE)
    {
      FILE_TYPE ftype_local;
      error_code = file_get_type (thread_p, &entry->hfid.vfid, &ftype_local);
      if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      lf_tran_end_with_mb (t_entry);
      return error_code;
    }
      entry->ftype = ftype_local;
    }
  assert (entry->ftype == FILE_HEAP || entry->ftype == FILE_HEAP_REUSE_SLOTS);

  if (hfid_out != NULL)
    {
      *hfid_out = entry->hfid;
    }
  if (ftype_out != NULL)
    {
      *ftype_out = entry->ftype;
    }

  lf_tran_end_with_mb (t_entry);
  return error_code;
}

/*
 * heap_page_update_chain_after_mvcc_op () - Update max MVCCID and vacuum
 *                       status in heap page chain after
 *                       an MVCC op is executed.
 *
 * return     : Void.
 * thread_p (in)  : Thread entry.
 * heap_page (in) : Heap page.
 * mvccid (in)    : MVCC op MVCCID.
 */
static void
heap_page_update_chain_after_mvcc_op (THREAD_ENTRY * thread_p, PAGE_PTR heap_page, MVCCID mvccid)
{
  HEAP_CHAIN *chain;
  RECDES chain_recdes;
  HEAP_PAGE_VACUUM_STATUS vacuum_status;

  assert (heap_page != NULL);
  assert (MVCCID_IS_NORMAL (mvccid));

  /* Two actions are being done here: 1. Update vacuum status.  - HEAP_PAGE_VACUUM_NONE + 1 mvcc op =>
   * HEAP_PAGE_VACUUM_ONCE - HEAP_PAGE_VACUUM_ONCE + 1 mvcc op => HEAP_PAGE_VACUUM_UNKNOWN (because future becomes
   * unpredictable).  - HEAP_PAGE_VACUUM_UNKNOWN + 1 mvcc op can we tell that page is vacuumed? =>
   * HEAP_PAGE_VACUUM_ONCE we don't know that page is vacuumed? => HEAP_PAGE_VACUUM_UNKNOWN 2. Update max MVCCID if
   * new MVCCID is bigger. */

  /* Get heap chain. */
  if (spage_get_record (thread_p, heap_page, HEAP_HEADER_AND_CHAIN_SLOTID, &chain_recdes, PEEK) != S_SUCCESS)
    {
      assert_release (false);
      return;
    }
  if (chain_recdes.length != sizeof (HEAP_CHAIN))
    {
      /* Heap header page. Do nothing. */
      assert (chain_recdes.length == sizeof (HEAP_HDR_STATS));
      return;
    }
  chain = (HEAP_CHAIN *) chain_recdes.data;

  /* Update vacuum status. */
  vacuum_status = HEAP_PAGE_GET_VACUUM_STATUS (chain);
  switch (vacuum_status)
    {
    case HEAP_PAGE_VACUUM_NONE:
      /* Change status to one vacuum. */
      assert (MVCC_ID_PRECEDES (chain->max_mvccid, mvccid));
      HEAP_PAGE_SET_VACUUM_STATUS (chain, HEAP_PAGE_VACUUM_ONCE);
      vacuum_er_log (VACUUM_ER_LOG_HEAP,
             "Changed vacuum status for page %d|%d, lsa=%lld|%d from no vacuum to vacuum once.",
             PGBUF_PAGE_STATE_ARGS (heap_page));
      break;

    case HEAP_PAGE_VACUUM_ONCE:
      /* Change status to unknown number of vacuums. */
      HEAP_PAGE_SET_VACUUM_STATUS (chain, HEAP_PAGE_VACUUM_UNKNOWN);
      vacuum_er_log (VACUUM_ER_LOG_HEAP,
             "Changed vacuum status for page %d|%d, lsa=%lld|%d from vacuum once to unknown.",
             PGBUF_PAGE_STATE_ARGS (heap_page));
      break;

    case HEAP_PAGE_VACUUM_UNKNOWN:
      /* Was page completely vacuumed? We can tell if current max_mvccid precedes vacuum data's oldest mvccid. */
      if (vacuum_is_mvccid_vacuumed (chain->max_mvccid))
    {
      /* Now page must be vacuumed once, due to new MVCC op. */
      HEAP_PAGE_SET_VACUUM_STATUS (chain, HEAP_PAGE_VACUUM_ONCE);
      vacuum_er_log (VACUUM_ER_LOG_HEAP,
             "Changed vacuum status for page %d|%d, lsa=%lld|%d from unknown to vacuum once.",
             PGBUF_PAGE_STATE_ARGS (heap_page));
    }
      else
    {
      /* Status remains the same. Number of vacuums needed still cannot be predicted. */
      vacuum_er_log (VACUUM_ER_LOG_HEAP, "Vacuum status for page %d|%d, %lld|%d remains unknown.",
             PGBUF_PAGE_STATE_ARGS (heap_page));
    }
      break;
    default:
      assert_release (false);
      break;
    }

  /* Update max_mvccid. */
  if (MVCC_ID_PRECEDES (chain->max_mvccid, mvccid))
    {
      vacuum_er_log (VACUUM_ER_LOG_HEAP, "Update max MVCCID for page %d|%d from %llu to %llu.",
             PGBUF_PAGE_VPID_AS_ARGS (heap_page), (unsigned long long int) chain->max_mvccid,
             (unsigned long long int) mvccid);
      chain->max_mvccid = mvccid;
    }
}

/*
 * heap_page_rv_vacuum_status_change () - Applies vacuum status change for
 *                    recovery.
 *
 * return     : Void.
 * thread_p (in)  : Thread entry.
 * heap_page (in) : Heap page.
 */
static void
heap_page_rv_chain_update (THREAD_ENTRY * thread_p, PAGE_PTR heap_page, MVCCID mvccid, bool vacuum_status_change)
{
  HEAP_CHAIN *chain;
  RECDES chain_recdes;
  HEAP_PAGE_VACUUM_STATUS vacuum_status;

  assert (heap_page != NULL);

  /* Possible transitions (see heap_page_update_chain_after_mvcc_op): - HEAP_PAGE_VACUUM_NONE => HEAP_PAGE_VACUUM_ONCE.
   * - HEAP_PAGE_VACUUM_ONCE => HEAP_PAGE_VACUUM_UNKNOWN. - HEAP_PAGE_VACUUM_UNKNOWN => HEAP_PAGE_VACUUM_ONCE. */

  /* Get heap chain. */
  if (spage_get_record (thread_p, heap_page, HEAP_HEADER_AND_CHAIN_SLOTID, &chain_recdes, PEEK) != S_SUCCESS)
    {
      assert_release (false);
      return;
    }
  if (chain_recdes.length != sizeof (HEAP_CHAIN))
    {
      /* Header page. Don't change chain. */
      return;
    }
  chain = (HEAP_CHAIN *) chain_recdes.data;

  if (vacuum_status_change)
    {
      /* Change status. */
      vacuum_status = HEAP_PAGE_GET_VACUUM_STATUS (chain);
      switch (vacuum_status)
    {
    case HEAP_PAGE_VACUUM_NONE:
    case HEAP_PAGE_VACUUM_UNKNOWN:
      HEAP_PAGE_SET_VACUUM_STATUS (chain, HEAP_PAGE_VACUUM_ONCE);

      vacuum_er_log (VACUUM_ER_LOG_HEAP | VACUUM_ER_LOG_RECOVERY,
             "Change heap page %d|%d, lsa=%lld|%d, status from %s to once.",
             PGBUF_PAGE_STATE_ARGS (heap_page),
             vacuum_status == HEAP_PAGE_VACUUM_NONE ? "none" : "unknown");
      break;
    case HEAP_PAGE_VACUUM_ONCE:
      HEAP_PAGE_SET_VACUUM_STATUS (chain, HEAP_PAGE_VACUUM_UNKNOWN);

      vacuum_er_log (VACUUM_ER_LOG_HEAP | VACUUM_ER_LOG_RECOVERY,
             "Change heap page %d|%d, lsa=%lld|%d, status from once to unknown.",
             PGBUF_PAGE_STATE_ARGS (heap_page));
      break;
    }
    }
  if (MVCC_ID_PRECEDES (chain->max_mvccid, mvccid))
    {
      chain->max_mvccid = mvccid;
    }
}

/*
 * heap_page_set_vacuum_status_none () - Change vacuum status from one vacuum
 *                   required to none.
 *
 * return     : Void.
 * thread_p (in)  : Thread entry.
 * heap_page (in) : Heap page.
 */
void
heap_page_set_vacuum_status_none (THREAD_ENTRY * thread_p, PAGE_PTR heap_page)
{
  HEAP_CHAIN *chain;
  RECDES chain_recdes;

  assert (heap_page != NULL);

  /* Updating vacuum status: - HEAP_PAGE_VACUUM_NONE => Vacuum is not expected. Fail. - HEAP_PAGE_VACUUM_ONCE + 1
   * vacuum => HEAP_PAGE_VACUUM_NONE. - HEAP_PAGE_VACUUM_UNKNOWN + 1 vacuum => HEAP_PAGE_VACUUM_UNKNOWN.  Number of
   * vacuums expected is unknown and remains that way. */

  /* Get heap chain. */
  if (spage_get_record (thread_p, heap_page, HEAP_HEADER_AND_CHAIN_SLOTID, &chain_recdes, PEEK) != S_SUCCESS)
    {
      assert_release (false);
      return;
    }
  if (chain_recdes.length != sizeof (HEAP_CHAIN))
    {
      /* Heap header page. */
      /* Should never be here. */
      assert_release (false);
      return;
    }
  chain = (HEAP_CHAIN *) chain_recdes.data;

  assert (HEAP_PAGE_GET_VACUUM_STATUS (chain) == HEAP_PAGE_VACUUM_ONCE);

  /* Update vacuum status. */
  HEAP_PAGE_SET_VACUUM_STATUS (chain, HEAP_PAGE_VACUUM_NONE);

  vacuum_er_log (VACUUM_ER_LOG_HEAP, "Changed vacuum status for page %d|%d from vacuum once to no vacuum.",
         PGBUF_PAGE_VPID_AS_ARGS (heap_page));
}

/*
 * heap_page_get_max_mvccid () - Get max MVCCID of heap page.
 *
 * return     : Max MVCCID.
 * thread_p (in)  : Thread entry.
 * heap_page (in) : Heap page.
 */
MVCCID
heap_page_get_max_mvccid (THREAD_ENTRY * thread_p, PAGE_PTR heap_page)
{
  HEAP_CHAIN *chain;
  RECDES chain_recdes;

  assert (heap_page != NULL);

  /* Get heap chain. */
  if (spage_get_record (thread_p, heap_page, HEAP_HEADER_AND_CHAIN_SLOTID, &chain_recdes, PEEK) != S_SUCCESS)
    {
      assert_release (false);
      return MVCCID_NULL;
    }
  if (chain_recdes.length != sizeof (HEAP_CHAIN))
    {
      /* Heap header page. */
      assert (chain_recdes.length == sizeof (HEAP_HDR_STATS));
      return MVCCID_NULL;
    }
  chain = (HEAP_CHAIN *) chain_recdes.data;

  return chain->max_mvccid;
}

/*
 * heap_page_get_vacuum_status () - Get heap page vacuum status.
 *
 * return     : Vacuum status.
 * thread_p (in)  : Thread entry.
 * heap_page (in) : Heap page.
 */
HEAP_PAGE_VACUUM_STATUS
heap_page_get_vacuum_status (THREAD_ENTRY * thread_p, PAGE_PTR heap_page)
{
  HEAP_CHAIN *chain;
  RECDES chain_recdes;

  assert (heap_page != NULL);

  /* Get heap chain. */
  if (spage_get_record (thread_p, heap_page, HEAP_HEADER_AND_CHAIN_SLOTID, &chain_recdes, PEEK) != S_SUCCESS)
    {
      assert_release (false);
      return HEAP_PAGE_VACUUM_UNKNOWN;
    }
  if (chain_recdes.length != sizeof (HEAP_CHAIN))
    {
      /* Heap header page. */
      assert (chain_recdes.length == sizeof (HEAP_HDR_STATS));
      return HEAP_PAGE_VACUUM_UNKNOWN;
    }
  chain = (HEAP_CHAIN *) chain_recdes.data;

  return HEAP_PAGE_GET_VACUUM_STATUS (chain);
}

/*
 * heap_rv_nop () - Heap recovery no op function.
 *
 * return    : NO_ERROR.
 * thread_p (in) : Thread entry.
 * rcv (in)  : Recovery data.
 */
int
heap_rv_nop (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  assert (rcv->pgptr != NULL);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return NO_ERROR;
}

/*
 * heap_rv_update_chain_after_mvcc_op () - Redo update of page chain after
 *                     an MVCC operation (used for
 *                     operations that are not changing
 *                     
 *
 * return    : NO_ERROR
 * thread_p (in) : Thread entry.
 * rcv (in)  : Recovery data.
 */
int
heap_rv_update_chain_after_mvcc_op (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  bool vacuum_status_change = false;

  assert (rcv->pgptr != NULL);
  assert (MVCCID_IS_NORMAL (rcv->mvcc_id));

  vacuum_status_change = (rcv->offset & HEAP_RV_FLAG_VACUUM_STATUS_CHANGE) != 0;
  heap_page_rv_chain_update (thread_p, rcv->pgptr, rcv->mvcc_id, vacuum_status_change);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);
  return NO_ERROR;
}

/*
 * heap_rv_remove_flags_from_offset () - Remove flags from recovery offset.
 *
 * return    : Offset without flags.
 * offset (in)   : Offset with flags.
 */
INT16
heap_rv_remove_flags_from_offset (INT16 offset)
{
  return offset & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
}

/*
 * heap_should_try_update_stat () - checks if an heap update statistics is
 *                  indicated
 *                     
 *
 * return    : NO_ERROR
 * thread_p (in) : Thread entry.
 * rcv (in)  : Recovery data.
 */
bool
heap_should_try_update_stat (const int current_freespace, const int prev_freespace)
{
  if (current_freespace > prev_freespace && current_freespace > HEAP_DROP_FREE_SPACE
      && prev_freespace < HEAP_DROP_FREE_SPACE)
    {
      return true;
    }
  return false;
}

/*
 * heap_scancache_add_partition_node () - add a new partition information to
 *                    to the scan_cache's partition list.
 *                    Also sets the current node of the
 *                    scancache to this newly inserted node.
 * 
 * return       : error code
 * thread_p (in)    :
 * scan_cache (in)  :
 * partition_oid (in)   :
 */
static int
heap_scancache_add_partition_node (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache, OID * partition_oid)
{
  HFID hfid;
  HEAP_SCANCACHE_NODE_LIST *new_ = NULL;

  assert (scan_cache != NULL);

  if (heap_get_hfid_from_class_oid (thread_p, partition_oid, &hfid) != NO_ERROR)
    {
      return ER_FAILED;
    }

  new_ = (HEAP_SCANCACHE_NODE_LIST *) db_private_alloc (thread_p, sizeof (HEAP_SCANCACHE_NODE_LIST));
  if (new_ == NULL)
    {
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, sizeof (HEAP_SCANCACHE_NODE_LIST));
      return ER_OUT_OF_VIRTUAL_MEMORY;
    }

  COPY_OID (&new_->node.class_oid, partition_oid);
  HFID_COPY (&new_->node.hfid, &hfid);
  if (scan_cache->partition_list == NULL)
    {
      new_->next = NULL;
      scan_cache->partition_list = new_;
    }
  else
    {
      new_->next = scan_cache->partition_list;
      scan_cache->partition_list = new_;
    }

  /* set the new node as the current node */
  HEAP_SCANCACHE_SET_NODE (scan_cache, partition_oid, &hfid);

  return NO_ERROR;
}

/*
 * heap_mvcc_log_redistribute () - Log partition redistribute data
 *
 * return    : Void.
 * thread_p (in) : Thread entry.
 * p_recdes (in) : Newly inserted record.
 * p_addr (in)   : Log address data.
 */
static void
heap_mvcc_log_redistribute (THREAD_ENTRY * thread_p, RECDES * p_recdes, LOG_DATA_ADDR * p_addr)
{
#define HEAP_LOG_MVCC_REDISTRIBUTE_MAX_REDO_CRUMBS      4

  int n_redo_crumbs = 0, data_copy_offset = 0;
  LOG_CRUMB redo_crumbs[HEAP_LOG_MVCC_REDISTRIBUTE_MAX_REDO_CRUMBS];
  MVCCID delid;
  MVCC_REC_HEADER mvcc_rec_header;
  HEAP_PAGE_VACUUM_STATUS vacuum_status;

  assert (p_recdes != NULL);
  assert (p_addr != NULL);

  vacuum_status = heap_page_get_vacuum_status (thread_p, p_addr->pgptr);

  /* Update chain. */
  heap_page_update_chain_after_mvcc_op (thread_p, p_addr->pgptr, logtb_get_current_mvccid (thread_p));
  if (vacuum_status != heap_page_get_vacuum_status (thread_p, p_addr->pgptr))
    {
      /* Mark status change for recovery. */
      p_addr->offset |= HEAP_RV_FLAG_VACUUM_STATUS_CHANGE;
    }

  /* Build redo crumbs */
  /* Add record type */
  redo_crumbs[n_redo_crumbs].length = sizeof (p_recdes->type);
  redo_crumbs[n_redo_crumbs++].data = &p_recdes->type;

  if (p_recdes->type != REC_BIGONE)
    {
      or_mvcc_get_header (p_recdes, &mvcc_rec_header);
      assert (MVCC_IS_FLAG_SET (&mvcc_rec_header, OR_MVCC_FLAG_VALID_DELID));

      /* Add representation ID and flags field */
      redo_crumbs[n_redo_crumbs].length = OR_INT_SIZE;
      redo_crumbs[n_redo_crumbs++].data = p_recdes->data;

      redo_crumbs[n_redo_crumbs].length = OR_MVCCID_SIZE;
      redo_crumbs[n_redo_crumbs++].data = &delid;

      /* Set data copy offset after the record header */
      data_copy_offset = OR_HEADER_SIZE (p_recdes->data);
    }

  /* Add record data - record may be skipped if the record is not big one */
  redo_crumbs[n_redo_crumbs].length = p_recdes->length - data_copy_offset;
  redo_crumbs[n_redo_crumbs++].data = p_recdes->data + data_copy_offset;

  /* Safe guard */
  assert (n_redo_crumbs <= HEAP_LOG_MVCC_REDISTRIBUTE_MAX_REDO_CRUMBS);

  /* Append redo crumbs; undo crumbs not necessary as the spage_delete physical operation uses the offset field of the
   * address */
  log_append_undoredo_crumbs (thread_p, RVHF_MVCC_REDISTRIBUTE, p_addr, 0, n_redo_crumbs, NULL, redo_crumbs);
}

/*
 * heap_rv_mvcc_redo_redistribute () - Redo the MVCC redistribute partition data
 *   return: int
 *   rcv(in): Recovery structure
 *
 */
int
heap_rv_mvcc_redo_redistribute (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  INT16 slotid;
  RECDES recdes;
  int sp_success;
  MVCCID delid;
  MVCC_REC_HEADER mvcc_rec_header;
  INT16 record_type;
  bool vacuum_status_change = false;

  assert (rcv->pgptr != NULL);

  slotid = rcv->offset;
  if (slotid & HEAP_RV_FLAG_VACUUM_STATUS_CHANGE)
    {
      vacuum_status_change = true;
    }
  slotid = slotid & (~HEAP_RV_FLAG_VACUUM_STATUS_CHANGE);
  assert (slotid > 0);

  record_type = *(INT16 *) rcv->data;
  if (record_type == REC_BIGONE)
    {
      /* no data header */
      HEAP_SET_RECORD (&recdes, rcv->length - sizeof (record_type), rcv->length - sizeof (record_type), REC_BIGONE,
               rcv->data + sizeof (record_type));
    }
  else
    {
      char data_buffer[IO_DEFAULT_PAGE_SIZE + OR_MVCC_MAX_HEADER_SIZE + MAX_ALIGNMENT];
      int repid_and_flags, offset, mvcc_flag, offset_size;

      offset = sizeof (record_type);

      repid_and_flags = OR_GET_INT (rcv->data + offset);
      offset += OR_INT_SIZE;

      OR_GET_MVCCID (rcv->data + offset, &delid);
      offset += OR_MVCCID_SIZE;

      mvcc_flag = (char) ((repid_and_flags >> OR_MVCC_FLAG_SHIFT_BITS) & OR_MVCC_FLAG_MASK);

      if ((repid_and_flags & OR_OFFSET_SIZE_FLAG) == OR_OFFSET_SIZE_1BYTE)
    {
      offset_size = OR_BYTE_SIZE;
    }
      else if ((repid_and_flags & OR_OFFSET_SIZE_FLAG) == OR_OFFSET_SIZE_2BYTE)
    {
      offset_size = OR_SHORT_SIZE;
    }
      else
    {
      offset_size = OR_INT_SIZE;
    }

      MVCC_SET_REPID (&mvcc_rec_header, repid_and_flags & OR_MVCC_REPID_MASK);
      MVCC_SET_FLAG (&mvcc_rec_header, mvcc_flag);
      MVCC_SET_INSID (&mvcc_rec_header, rcv->mvcc_id);
      MVCC_SET_DELID (&mvcc_rec_header, delid);

      HEAP_SET_RECORD (&recdes, IO_DEFAULT_PAGE_SIZE + OR_MVCC_MAX_HEADER_SIZE, 0, record_type,
               PTR_ALIGN (data_buffer, MAX_ALIGNMENT));
      or_mvcc_add_header (&recdes, &mvcc_rec_header, repid_and_flags & OR_BOUND_BIT_FLAG, offset_size);

      memcpy (recdes.data + recdes.length, rcv->data + offset, rcv->length - offset);
      recdes.length += (rcv->length - offset);
    }

  sp_success = spage_insert_for_recovery (thread_p, rcv->pgptr, slotid, &recdes);

  if (sp_success != SP_SUCCESS)
    {
      /* Unable to redo insertion */
      assert_release (false);
      return ER_FAILED;
    }

  heap_page_rv_chain_update (thread_p, rcv->pgptr, rcv->mvcc_id, vacuum_status_change);
  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return NO_ERROR;
}

/*
 * heap_get_visible_version_from_log () - Iterate through old versions of object until a visible object is found
 *                  
 *   return: SCAN_CODE. Possible values: 
 *       - S_SUCCESS: for successful case when record was obtained.
 *       - S_DOESNT_EXIT: NULL LSA was provided, otherwise a visible version should exist
 *       - S_DOESNT_FIT: the record doesn't fit in allocated area
 *       - S_ERROR: In case of error
 *   thread_p (in): Thread entry.
 *   recdes (out): Record descriptor.
 *   previous_version_lsa (in): Log address of previous version.
 *   scan_cache(in): Heap scan cache.
 */
static SCAN_CODE
heap_get_visible_version_from_log (THREAD_ENTRY * thread_p, RECDES * recdes, LOG_LSA * previous_version_lsa,
                   HEAP_SCANCACHE * scan_cache, int has_chn)
{
  LOG_LSA process_lsa;
  SCAN_CODE scan_code = S_SUCCESS;
  char log_pgbuf[IO_MAX_PAGE_SIZE + MAX_ALIGNMENT];
  LOG_PAGE *log_page_p = NULL;
  MVCC_REC_HEADER mvcc_header;
  RECDES local_recdes;
  MVCC_SATISFIES_SNAPSHOT_RESULT snapshot_res;
  LOG_LSA oldest_prior_lsa;

  assert (scan_cache != NULL);
  assert (scan_cache->mvcc_snapshot != NULL);

  if (recdes == NULL)
    {
      recdes = &local_recdes;
      recdes->data = NULL;
    }

  /* make sure prev_version_lsa is flushed from prior lsa list - wake up log flush thread if it's not flushed */
  oldest_prior_lsa = *log_get_append_lsa ();    /* TODO: fix atomicity issue on x86 */
  if (LSA_LT (&oldest_prior_lsa, previous_version_lsa))
    {
      LOG_CS_ENTER (thread_p);
      logpb_prior_lsa_append_all_list (thread_p);
      LOG_CS_EXIT (thread_p);

      oldest_prior_lsa = *log_get_append_lsa ();
      assert (!LSA_LT (&oldest_prior_lsa, previous_version_lsa));
    }

  if (recdes->data == NULL)
    {
      if (scan_cache->area == NULL)
    {
      /* Allocate an area to hold the object. Assume that the object will fit in two pages for not better
       * estimates. */
      scan_cache->area_size = DB_PAGESIZE * 2;
      scan_cache->area = (char *) db_private_alloc (thread_p, scan_cache->area_size);
      if (scan_cache->area == NULL)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, scan_cache->area_size);
          scan_cache->area_size = -1;
          return S_ERROR;
        }
    }
      recdes->data = scan_cache->area;
      recdes->area_size = scan_cache->area_size;
    }

  /* check visibility of old versions from log following prev_version_lsa links */
  for (LSA_COPY (&process_lsa, previous_version_lsa); !LSA_ISNULL (&process_lsa);)
    {
      /* Fetch the page where prev_vesion_lsa is located */
      log_page_p = (LOG_PAGE *) PTR_ALIGN (log_pgbuf, MAX_ALIGNMENT);
      log_page_p->hdr.logical_pageid = NULL_PAGEID;
      log_page_p->hdr.offset = NULL_OFFSET;
      if (logpb_fetch_page (thread_p, &process_lsa, LOG_CS_SAFE_READER, log_page_p) != NO_ERROR)
    {
      assert (false);
      logpb_fatal_error (thread_p, true, ARG_FILE_LINE, "heap_get_visible_version_from_log");
      return S_ERROR;
    }

      scan_code = log_get_undo_record (thread_p, log_page_p, process_lsa, recdes);
      if (scan_code != S_SUCCESS)
    {
      if (scan_code == S_DOESNT_FIT && recdes->data == scan_cache->area)
        {
          /* expand record area and try again */
          recdes->data = (char *) db_private_realloc (thread_p, scan_cache->area, -recdes->length);
          if (recdes->data == NULL)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, -recdes->length);
          return S_ERROR;
        }
          recdes->area_size = scan_cache->area_size = -recdes->length;
          scan_cache->area = recdes->data;

          /* final try to get the undo record */
          continue;
        }
      else
        {
          return scan_code;
        }
    }

      if (or_mvcc_get_header (recdes, &mvcc_header) != NO_ERROR)
    {
      assert (false);
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      return S_ERROR;
    }
      snapshot_res = scan_cache->mvcc_snapshot->snapshot_fnc (thread_p, &mvcc_header, scan_cache->mvcc_snapshot);
      if (snapshot_res == SNAPSHOT_SATISFIED)
    {
      /* Visible. Get record if CHN was changed. */
      if (MVCC_IS_CHN_UPTODATE (&mvcc_header, has_chn))
        {
          return S_SUCCESS_CHN_UPTODATE;
        }
      return S_SUCCESS;
    }
      else if (snapshot_res == TOO_OLD_FOR_SNAPSHOT)
    {
      assert (false);
      er_set (ER_FATAL_ERROR_SEVERITY, ARG_FILE_LINE, ER_GENERIC_ERROR, 0);
      return S_ERROR;
    }
      else
    {
      /* TOO_NEW_FOR_SNAPSHOT */
      assert (snapshot_res == TOO_NEW_FOR_SNAPSHOT);
      /* continue with previous version */
      LSA_COPY (&process_lsa, &MVCC_GET_PREV_VERSION_LSA (&mvcc_header));
      continue;
    }
    }

  /* No visible version found. */
  return S_DOESNT_EXIST;
}


/*
 * heap_get_visible_version () - get visible version, mvcc style when snapshot provided, otherwise directly from heap
 *
 *   return: SCAN_CODE. Posible values: 
 *       - S_SUCCESS: for successful case when record was obtained.
 *       - S_DOESNT_EXIT: 
 *       - S_DOESNT_FIT: the record doesn't fit in allocated area
 *       - S_ERROR: In case of error
 *       - S_SNAPSHOT_NOT_SATISFIED
 *       - S_SUCCESS_CHN_UPTODATE: CHN is up to date and it's not necessary to get record again
 *   thread_p (in): Thread entry.
 *   oid (in): Object to be obtained.
 *   class_oid (in): 
 *   recdes (out): Record descriptor. NULL if not needed
 *   scan_cache(in): Heap scan cache.
 *   ispeeking(in): Peek record or copy.
 *   old_chn (in): Cache coherency number for existing record data. It is
 *         used by clients to avoid resending record data when
 *         it was not updated.
 *  Note: this function should not be used for heap scan;
 */
SCAN_CODE
heap_get_visible_version (THREAD_ENTRY * thread_p, const OID * oid, OID * class_oid, RECDES * recdes,
              HEAP_SCANCACHE * scan_cache, int ispeeking, int old_chn)
{
  SCAN_CODE scan = S_SUCCESS;
  HEAP_GET_CONTEXT context;

  heap_init_get_context (thread_p, &context, oid, class_oid, recdes, scan_cache, ispeeking, old_chn);

  scan = heap_get_visible_version_internal (thread_p, &context, false);

  heap_clean_get_context (thread_p, &context);

  return scan;
}

/*
* heap_scan_get_visible_version () - get visible version, mvcc style when snapshot provided, otherwise directly from heap
*
*   return: SCAN_CODE. Posible values:
*        - S_SUCCESS: for successful case when record was obtained.
*        - S_DOESNT_EXIT:
*        - S_DOESNT_FIT: the record doesn't fit in allocated area
*        - S_ERROR: In case of error
*        - S_SNAPSHOT_NOT_SATISFIED
*        - S_SUCCESS_CHN_UPTODATE: CHN is up to date and it's not necessary to get record again
*   thread_p (in): Thread entry.
*   oid (in): Object to be obtained.
*   class_oid (in):
*   recdes (out): Record descriptor. NULL if not needed
*   scan_cache(in): Heap scan cache.
*   ispeeking(in): Peek record or copy.
*   old_chn (in): Cache coherency number for existing record data. It is
*          used by clients to avoid resending record data when
*          it was not updated.
*  Note: this function should be used for heap scan;
*/
SCAN_CODE
heap_scan_get_visible_version (THREAD_ENTRY * thread_p, const OID * oid, OID * class_oid, RECDES * recdes,
                   HEAP_SCANCACHE * scan_cache, int ispeeking, int old_chn)
{
  SCAN_CODE scan = S_SUCCESS;
  HEAP_GET_CONTEXT context;

  heap_init_get_context (thread_p, &context, oid, class_oid, recdes, scan_cache, ispeeking, old_chn);

  scan = heap_get_visible_version_internal (thread_p, &context, true);

  heap_clean_get_context (thread_p, &context);

  return scan;
}

/*
 * heap_get_visible_version_internal () - Retrieve the visible version of an object according to snapshot 
 * 
 *  return SCAN_CODE.
 *  thread_p (in): Thread entry.
 *  context (in): Heap get context. 
 *  is_heap_scan (in): required for heap_prepare_get_context
 */
SCAN_CODE
heap_get_visible_version_internal (THREAD_ENTRY * thread_p, HEAP_GET_CONTEXT * context, bool is_heap_scan)
{
  SCAN_CODE scan;

  MVCC_SNAPSHOT *mvcc_snapshot = NULL;
  MVCC_REC_HEADER mvcc_header = MVCC_REC_HEADER_INITIALIZER;
  OID class_oid_local = OID_INITIALIZER;

  assert (context->scan_cache != NULL);

  if (context->class_oid_p == NULL)
    {
      /* we need class_oid to check if the class is mvcc enabled */
      context->class_oid_p = &class_oid_local;
    }

  if (context->scan_cache && context->ispeeking == COPY && context->recdes_p != NULL)
    {
      /* Allocate an area to hold the object. Assume that the object will fit in two pages for not better estimates. */
      if (heap_scan_cache_allocate_area (thread_p, context->scan_cache, DB_PAGESIZE * 2) != NO_ERROR)
    {
      return S_ERROR;
    }
    }

  scan = heap_prepare_get_context (thread_p, context, is_heap_scan, LOG_WARNING_IF_DELETED);
  if (scan != S_SUCCESS)
    {
      goto exit;
    }
  assert (context->record_type == REC_HOME || context->record_type == REC_BIGONE
      || context->record_type == REC_RELOCATION);
  assert (context->record_type == REC_HOME
      || (!OID_ISNULL (&context->forward_oid) && context->fwd_page_watcher.pgptr != NULL));

  if (context->scan_cache != NULL && context->scan_cache->mvcc_snapshot != NULL
      && context->scan_cache->mvcc_snapshot->snapshot_fnc != NULL
      && !mvcc_is_mvcc_disabled_class (context->class_oid_p))
    {
      mvcc_snapshot = context->scan_cache->mvcc_snapshot;
    }

  if (mvcc_snapshot != NULL || context->old_chn != NULL_CHN)
    {
      /* mvcc header is needed for visibility check or chn check */
      scan = heap_get_mvcc_header (thread_p, context, &mvcc_header);
      if (scan != S_SUCCESS)
    {
      goto exit;
    }
    }

  if (mvcc_snapshot != NULL)
    {
      MVCC_SATISFIES_SNAPSHOT_RESULT snapshot_res;

      snapshot_res = mvcc_snapshot->snapshot_fnc (thread_p, &mvcc_header, mvcc_snapshot);
      if (snapshot_res == TOO_NEW_FOR_SNAPSHOT)
    {
      /* current version is not visible, check previous versions from log and skip record get from heap */
      scan =
        heap_get_visible_version_from_log (thread_p, context->recdes_p, &MVCC_GET_PREV_VERSION_LSA (&mvcc_header),
                           context->scan_cache, context->old_chn);
      goto exit;
    }
      else if (snapshot_res == TOO_OLD_FOR_SNAPSHOT)
    {
      scan = S_SNAPSHOT_NOT_SATISFIED;
      goto exit;
    }
      /* else...fall through to heap get */
    }

  if (MVCC_IS_CHN_UPTODATE (&mvcc_header, context->old_chn))
    {
      /* Object version didn't change and CHN is up-to-date. Don't get record data and return
       * S_SUCCESS_CHN_UPTODATE instead. */
      scan = S_SUCCESS_CHN_UPTODATE;
      goto exit;
    }

  if (context->recdes_p != NULL)
    {
      scan = heap_get_record_data_when_all_ready (thread_p, context);
    }

  /* Fall through to exit. */

exit:
  return scan;
}

/*
 * heap_update_set_prev_version () - Set prev version lsa to record according to its type. 
 *
 * return          : error code or NO_ERROR
 * thread_p (in)       : Thread entry.
 * oid (in)            : Object identifier of the updated record
 * home_pg_watcher (in): Home page watcher; must be  
 * fwd_pg_watcher (in) : Forward page watcher
 * prev_version_lsa(in): LSA address of undo log record of the old record
 *
 * Note: This function works only with heap_update_home/relocation/bigone functions. It is designed to set the 
 *       prev_version_lsa to updated records by overwriting this information directly into heap file. The header of the
 *       record should be prepared for this in heap_insert_adjust_recdes_header().
 *       The records are obtained using PEEK, and modified directly, without using spage_update afterwards!
 * Note: It is expected to have the home page fixed and also the forward page in case of relocation.
 */
static int
heap_update_set_prev_version (THREAD_ENTRY * thread_p, const OID * oid, PGBUF_WATCHER * home_pg_watcher,
                  PGBUF_WATCHER * fwd_pg_watcher, LOG_LSA * prev_version_lsa)
{
  int error_code = NO_ERROR;
  RECDES recdes, forward_recdes;
  VPID fwd_vpid;
  OID forward_oid;
  PGBUF_WATCHER overflow_pg_watcher;

  assert (oid != NULL && !OID_ISNULL (oid) && prev_version_lsa != NULL && !LSA_ISNULL (prev_version_lsa));
  assert (prev_version_lsa->pageid > 0 && prev_version_lsa->offset >= 0);

  /* the home page should be already fixed */
  assert (home_pg_watcher != NULL && home_pg_watcher->pgptr != NULL);
  if (spage_get_record (thread_p, home_pg_watcher->pgptr, oid->slotid, &recdes, PEEK) != S_SUCCESS)
    {
      ASSERT_ERROR_AND_SET (error_code);
      goto end;
    }

  if (recdes.type == REC_HOME)
    {
      error_code = or_mvcc_set_log_lsa_to_record (&recdes, prev_version_lsa);
      if (error_code != NO_ERROR)
    {
      assert (false);
      goto end;
    }

      pgbuf_set_dirty (thread_p, home_pg_watcher->pgptr, DONT_FREE);
    }
  else if (recdes.type == REC_RELOCATION)
    {
      forward_oid = *((OID *) recdes.data);
      VPID_GET_FROM_OID (&fwd_vpid, &forward_oid);

      /* the forward page should be already fixed */
      assert (fwd_pg_watcher != NULL && fwd_pg_watcher->pgptr != NULL);
      assert (VPID_EQ (&fwd_vpid, pgbuf_get_vpid_ptr (fwd_pg_watcher->pgptr)));

      if (spage_get_record (thread_p, fwd_pg_watcher->pgptr, forward_oid.slotid, &forward_recdes, PEEK) != S_SUCCESS)
    {
      ASSERT_ERROR_AND_SET (error_code);
      goto end;
    }

      error_code = or_mvcc_set_log_lsa_to_record (&forward_recdes, prev_version_lsa);
      if (error_code != NO_ERROR)
    {
      assert (false);
      goto end;
    }

      pgbuf_set_dirty (thread_p, fwd_pg_watcher->pgptr, DONT_FREE);
    }
  else if (recdes.type == REC_BIGONE)
    {
      forward_oid = *((OID *) recdes.data);

      VPID_GET_FROM_OID (&fwd_vpid, &forward_oid);
      PGBUF_INIT_WATCHER (&overflow_pg_watcher, PGBUF_ORDERED_HEAP_NORMAL, PGBUF_ORDERED_NULL_HFID);
      PGBUF_WATCHER_COPY_GROUP (&overflow_pg_watcher, home_pg_watcher);
      if (pgbuf_ordered_fix (thread_p, &fwd_vpid, OLD_PAGE, PGBUF_LATCH_WRITE, &overflow_pg_watcher) != NO_ERROR)
    {
      ASSERT_ERROR_AND_SET (error_code);
      goto end;
    }

      forward_recdes.data = overflow_get_first_page_data (overflow_pg_watcher.pgptr);
      forward_recdes.length = OR_HEADER_SIZE (forward_recdes.data);

      error_code = or_mvcc_set_log_lsa_to_record (&forward_recdes, prev_version_lsa);

      /* unfix overflow page; it is used only locally */
      pgbuf_set_dirty (thread_p, overflow_pg_watcher.pgptr, DONT_FREE);
      pgbuf_ordered_unfix (thread_p, &overflow_pg_watcher);

      if (error_code != NO_ERROR)
    {
      assert (false);
      goto end;
    }
    }
  else
    {
      /* Unexpected record type. */
      assert (false);
      error_code = ER_FAILED;
    }

end:
  return error_code;
}

/*
 * heap_get_last_version () - Generic function for retrieving last version of heap objects (not considering visibility)
 *
 * return    : Scan code.
 * thread_p (in) : Thread entry.
 * context (in) : Heap get context
 *
 * NOTE: Caller must handle the cleanup of context
 */
SCAN_CODE
heap_get_last_version (THREAD_ENTRY * thread_p, HEAP_GET_CONTEXT * context)
{
  SCAN_CODE scan = S_SUCCESS;
  MVCC_REC_HEADER mvcc_header = MVCC_REC_HEADER_INITIALIZER;

  assert (context->scan_cache != NULL);
  assert (context->recdes_p != NULL);

  if (context->scan_cache && context->ispeeking == COPY)
    {
      /* Allocate an area to hold the object. Assume that the object will fit in two pages for not better estimates. */
      if (heap_scan_cache_allocate_area (thread_p, context->scan_cache, DB_PAGESIZE * 2) != NO_ERROR)
    {
      return S_ERROR;
    }
    }

  scan = heap_prepare_get_context (thread_p, context, false, LOG_WARNING_IF_DELETED);
  if (scan != S_SUCCESS)
    {
      goto exit;
    }
  assert (context->record_type == REC_HOME || context->record_type == REC_BIGONE
      || context->record_type == REC_RELOCATION);
  assert (context->record_type == REC_HOME
      || (!OID_ISNULL (&context->forward_oid) && context->fwd_page_watcher.pgptr != NULL));

  scan = heap_get_mvcc_header (thread_p, context, &mvcc_header);
  if (scan != S_SUCCESS)
    {
      goto exit;
    }

  if (MVCC_IS_CHN_UPTODATE (&mvcc_header, context->old_chn))
    {
      /* Object version didn't change and CHN is up-to-date. Don't get record data and return
       * S_SUCCESS_CHN_UPTODATE instead. */
      scan = S_SUCCESS_CHN_UPTODATE;
      goto exit;
    }

  if (context->recdes_p != NULL)
    {
      scan = heap_get_record_data_when_all_ready (thread_p, context);
    }

  /* Fall through to exit. */

exit:

  return scan;
}

/* 
 * heap_prepare_object_page () - Check if provided page matches the page of provided OID or fix the right one.
 *
 * return          : Error code.
 * thread_p (in)       : Thread entry.
 * oid (in)        : Object identifier.
 * page_watcher_p(out) : Page watcher used for page fix.
 * latch_mode (in)     : Latch mode.
 */
int
heap_prepare_object_page (THREAD_ENTRY * thread_p, const OID * oid, PGBUF_WATCHER * page_watcher_p,
              PGBUF_LATCH_MODE latch_mode)
{
  VPID object_vpid;
  int ret = NO_ERROR;

  assert (oid != NULL && !OID_ISNULL (oid));

  VPID_GET_FROM_OID (&object_vpid, oid);

  if (page_watcher_p->pgptr != NULL && !VPID_EQ (pgbuf_get_vpid_ptr (page_watcher_p->pgptr), &object_vpid))
    {
      /* unfix provided page if it does not correspond to the VPID */
      pgbuf_ordered_unfix (thread_p, page_watcher_p);
    }

  if (page_watcher_p->pgptr == NULL)
    {
      /* fix required page */
      ret = pgbuf_ordered_fix (thread_p, &object_vpid, OLD_PAGE, latch_mode, page_watcher_p);
      if (ret != NO_ERROR)
    {
      if (ret == ER_PB_BAD_PAGEID)
        {
          /* maybe this error could be removed */
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_HEAP_UNKNOWN_OBJECT, 3, oid->volid, oid->pageid,
              oid->slotid);
          ret = ER_HEAP_UNKNOWN_OBJECT;
        }

      if (ret == ER_LK_PAGE_TIMEOUT && er_errid () == NO_ERROR)
        {
          er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_PAGE_LATCH_ABORTED, 2, oid->volid, oid->pageid);
          ret = ER_PAGE_LATCH_ABORTED;
        }
    }
    }

  return ret;
}

/* 
 * heap_clean_get_context () - Unfix page watchers of get context and save home page to scan_cache if possible 
 * 
 * thread_p (in)   : Thread_identifier.
 * context (in)    : Heap get context.
 */
void
heap_clean_get_context (THREAD_ENTRY * thread_p, HEAP_GET_CONTEXT * context)
{
  assert (context != NULL);

  if (context->scan_cache != NULL && context->scan_cache->cache_last_fix_page
      && context->home_page_watcher.pgptr != NULL)
    {
      /* Save home page (or NULL if it had to be unfixed) to scan_cache. */
      pgbuf_replace_watcher (thread_p, &context->home_page_watcher, &context->scan_cache->page_watcher);
      assert (context->home_page_watcher.pgptr == NULL);
    }

  if (context->home_page_watcher.pgptr)
    {
      /* Unfix home page. */
      pgbuf_ordered_unfix (thread_p, &context->home_page_watcher);
    }

  if (context->fwd_page_watcher.pgptr != NULL)
    {
      /* Unfix forward page. */
      pgbuf_ordered_unfix (thread_p, &context->fwd_page_watcher);
    }

  assert (context->home_page_watcher.pgptr == NULL && context->fwd_page_watcher.pgptr == NULL);
}

/* 
 * heap_init_get_context () - Initiate all heap get context fields with generic informations
 *
 * thread_p (in)   : Thread_identifier.
 * context (out)   : Heap get context.
 * oid (in)    : Object identifier.
 * class_oid (in)  : Class oid.
 * recdes (in)     : Record descriptor.
 * scan_cache (in) : Scan cache. 
 * is_peeking (in) : PEEK or COPY.
 * old_chn (in)    : Cache coherency number. 
*/
void
heap_init_get_context (THREAD_ENTRY * thread_p, HEAP_GET_CONTEXT * context, const OID * oid, OID * class_oid,
               RECDES * recdes, HEAP_SCANCACHE * scan_cache, int ispeeking, int old_chn)
{
  context->oid_p = oid;
  context->class_oid_p = class_oid;
  OID_SET_NULL (&context->forward_oid);
  context->recdes_p = recdes;

  if (scan_cache != NULL && !HFID_IS_NULL (&scan_cache->node.hfid))
    {
      PGBUF_INIT_WATCHER (&context->home_page_watcher, PGBUF_ORDERED_HEAP_NORMAL, &scan_cache->node.hfid);
      PGBUF_INIT_WATCHER (&context->fwd_page_watcher, PGBUF_ORDERED_HEAP_NORMAL, &scan_cache->node.hfid);
    }
  else
    {
      PGBUF_INIT_WATCHER (&context->home_page_watcher, PGBUF_ORDERED_HEAP_NORMAL, PGBUF_ORDERED_NULL_HFID);
      PGBUF_INIT_WATCHER (&context->fwd_page_watcher, PGBUF_ORDERED_HEAP_NORMAL, PGBUF_ORDERED_NULL_HFID);
    }

  if (scan_cache != NULL && scan_cache->cache_last_fix_page && scan_cache->page_watcher.pgptr != NULL)
    {
      /* switch to local page watcher */
      pgbuf_replace_watcher (thread_p, &scan_cache->page_watcher, &context->home_page_watcher);
    }

  context->scan_cache = scan_cache;
  context->ispeeking = ispeeking;
  context->old_chn = old_chn;
  if (scan_cache != NULL && scan_cache->page_latch == X_LOCK)
    {
      context->latch_mode = PGBUF_LATCH_WRITE;
    }
  else
    {
      context->latch_mode = PGBUF_LATCH_READ;
    }
}

/*
 * heap_scan_cache_allocate_area () - Allocate scan_cache area
 *
 * return: error code
 * thread_p (in) : Thread entry.
 * scan_cache_p (in) : Scan cache.
 * size (in) : Required size of recdes data.
 */
int
heap_scan_cache_allocate_area (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache_p, int size)
{
  assert (scan_cache_p != NULL && size > 0);
  if (scan_cache_p->area == NULL)
    {
      /* Allocate an area to hold the object. Assume that the object will fit in two pages for not better estimates. */
      scan_cache_p->area = (char *) db_private_alloc (thread_p, size);
      if (scan_cache_p->area == NULL)
    {
      scan_cache_p->area_size = -1;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, size);
      return ER_OUT_OF_VIRTUAL_MEMORY;
    }
      scan_cache_p->area_size = size;
    }
  else if (scan_cache_p->area_size < size)
    {
      scan_cache_p->area = (char *) db_private_realloc (thread_p, scan_cache_p->area, size);
      if (scan_cache_p->area == NULL)
    {
      scan_cache_p->area_size = -1;
      er_set (ER_ERROR_SEVERITY, ARG_FILE_LINE, ER_OUT_OF_VIRTUAL_MEMORY, 1, size);
      return ER_OUT_OF_VIRTUAL_MEMORY;
    }
      scan_cache_p->area_size = size;
    }

  return NO_ERROR;
}

/*
 * heap_scan_cache_allocate_recdes_data () - Allocate recdes data and set it to recdes
 * 
 * return: error code 
 * thread_p (in) : Thread entry.
 * scan_cache_p (in) : Scan cache.
 * recdes_p (in) : Record descriptor.
 * size (in) : Required size of recdes data.
 */
static int
heap_scan_cache_allocate_recdes_data (THREAD_ENTRY * thread_p, HEAP_SCANCACHE * scan_cache_p, RECDES * recdes_p,
                      int size)
{
  int error_code;
  assert (scan_cache_p != NULL && recdes_p != NULL);

  error_code = heap_scan_cache_allocate_area (thread_p, scan_cache_p, size);
  if (error_code != NO_ERROR)
    {
      return error_code;
    }

  recdes_p->data = scan_cache_p->area;
  recdes_p->area_size = scan_cache_p->area_size;

  return NO_ERROR;
}

/*
 * heap_get_class_record () - Retrieves class objects only
 * 
 * return SCAN_CODE: S_SUCCESS or error
 * thread_p (in)   : Thread entry.
 * class_oid (in)  : Class object identifier.
 * recdes_p (out)  : Record descriptor.
 * scan_cache (in) : Scan cache.
 * ispeeking (in)  : PEEK or COPY
 */
SCAN_CODE
heap_get_class_record (THREAD_ENTRY * thread_p, const OID * class_oid, RECDES * recdes_p, HEAP_SCANCACHE * scan_cache,
               int ispeeking)
{
  HEAP_GET_CONTEXT context;
  OID root_oid = *oid_Root_class_oid;
  SCAN_CODE scan;

#if !defined(NDEBUG)
  /* for debugging set root_oid NULL and check afterwards if it really is root oid */
  OID_SET_NULL (&root_oid);
#endif /* !NDEBUG */
  heap_init_get_context (thread_p, &context, class_oid, &root_oid, recdes_p, scan_cache, ispeeking, NULL_CHN);

  scan = heap_get_last_version (thread_p, &context);

  heap_clean_get_context (thread_p, &context);

#if !defined(NDEBUG)
  assert (OID_ISNULL (&root_oid) || OID_IS_ROOTOID (&root_oid));
#endif /* !NDEBUG */

  return scan;
}

/*
 * heap_rv_undo_ovf_update - Assure undo record corresponds with vacuum status
 *
 * return   : int
 * thread_p (in): Thread entry.
 * rcv (in)     : Recovery structure.
 */
int
heap_rv_undo_ovf_update (THREAD_ENTRY * thread_p, LOG_RCV * rcv)
{
  int error_code;

  error_code = vacuum_rv_check_at_undo (thread_p, rcv->pgptr, NULL_SLOTID, REC_BIGONE);

  pgbuf_set_dirty (thread_p, rcv->pgptr, DONT_FREE);

  return error_code;
}

/*
 * heap_get_best_space_num_stats_entries - Returns the number of num_stats_entries 
 * return : the number of entries in the heap
 *
 */
int
heap_get_best_space_num_stats_entries (void)
{
  return heap_Bestspace->num_stats_entries;
}

/*
 * heap_get_hfid_from_vfid () - Get hfid for file. Caller must be sure this file belong to a heap.
 *
 * return        : error code
 * thread_p (in) : thread entry
 * vfid (in)     : file identifier
 * hfid (out)    : heap identifier
 */
int
heap_get_hfid_from_vfid (THREAD_ENTRY * thread_p, const VFID * vfid, HFID * hfid)
{
  VPID vpid_header;
  int error_code = NO_ERROR;

  hfid->vfid = *vfid;
  error_code = heap_get_header_page (thread_p, hfid, &vpid_header);
  if (error_code != NO_ERROR)
    {
      ASSERT_ERROR ();
      VFID_SET_NULL (&hfid->vfid);
      return error_code;
    }
  assert (hfid->vfid.volid == vpid_header.volid);
  hfid->hpgid = vpid_header.pageid;
  return NO_ERROR;
}

/*
 * heap_is_page_header () - return true if page is a heap header page. must be heap page though!
 *
 * return        : true if file header page, false otherwise.
 * thread_p (in) : thread entry
 * page (in)     : heap page
 */
bool
heap_is_page_header (THREAD_ENTRY * thread_p, PAGE_PTR page)
{
  SPAGE_HEADER *spage_header;
  SPAGE_SLOT *slotp;

  /* todo: why not set a different page ptype. */

  assert (page != NULL && pgbuf_get_page_ptype (thread_p, page) == PAGE_HEAP);

  spage_header = (SPAGE_HEADER *) page;
  if (spage_header->num_records <= 0)
    {
      return false;
    }
  slotp = spage_get_slot (page, HEAP_HEADER_AND_CHAIN_SLOTID);
  if (slotp == NULL)
    {
      return false;
    }
  if (slotp->record_length == sizeof (HEAP_HDR_STATS))
    {
      return true;
    }
  return false;
}